Systems and methods for detecting biodiesel in fuel

Abstract

A method of determining a presence of biodiesel in a fuel system includes receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component. The method includes determining an actual exotherm value regarding the first component based on the first temperature and the second temperature. The method includes enabling a first flag based on the actual exotherm value. The method includes receiving an expected temperature regarding the outlet of the first component. The method includes determining an expected exotherm value regarding the first component. The method includes enabling a second flag based on the expected exotherm value and the actual exotherm value. The method includes enabling a biodiesel detection flag responsive to enabling at least the first flag and the second flag.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This Applications claims the benefit of and priority to Indian Provisional Application No. 202441068032 filed September 9, 2024, which is incorporated herein by reference in its entirety and for all purposes.FIELD

[0002] The present disclosure relates generally to systems and methods for detecting biodiesel in fuel systems.BACKGROUND

[0003] Biodiesel is a renewable biofuel derived from biological sources, such as vegetable oils, animal fats, and / or recycled greases. Biodiesel may be or include long-chain fatty acid esters. Biodiesel may be used as fuel in internal combustion engine systems. In some internal combustion engine systems, the biodiesel may include a blend of biodiesel and a hydrocarbon-based diesel, commonly referred to as a "petrodiesel." A blend of biodiesel and petrodiesel having 20% or less biodiesel can be used in conventional internal combustion engine systems, with limited modifications to the internal combustion engine systems.SUMMARY

[0004] One embodiment relates to a method of determining a presence of biodiesel in a fuel system. The method includes: receiving, by at least one processor, one or more enable conditions regarding at least one of an engine system coupled to the fuel system or an aftertreatment system coupled to the engine system; and responsive to receiving the one or more enable conditions, executing an exotherm logic by the at least one processor to perform operations including: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component, based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of the presence of biodiesel in the fuel system.

[0005] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: receiving a fueling value regarding a regeneration event; and responsive to determining that the fueling value is at or above a fourth predefined threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0006] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including enabling a third flag responsive to determining that the first temperature is at or below a fourth predefined threshold. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0007] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a fourth predefined threshold; and responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0008] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: receiving a regeneration event stage of a regeneration event; and responsive to the regeneration event stage being during or after a predefined regeneration stage, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0009] In some embodiments, receiving the one or more enable conditions includes receiving an indication of an amount of time that the first component of the aftertreatment system has been operating is at or below a fourth predefined threshold.

[0010] In some embodiments, receiving the one or more enable conditions includes receiving an indication that an efficiency value of the first component is at or above a predefined threshold.

[0011] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: responsive to enabling the biodiesel detection flag, incrementing a biodiesel detection counter value; and responsive to the biodiesel detection counter value being at or above a predetermined biodiesel detection counter threshold, generating the indication of the presence of biodiesel in the fuel system.

[0012] Another embodiment relates to a system. The system includes a controller coupled to an engine, a fuel system, and an aftertreatment system, the controller including one or more processors and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations. The operations include: receiving one or more enable conditions regarding at least one of the engine, the fuel system, or the aftertreatment system; and responsive to receiving the one or more enable conditions: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of a presence of biodiesel in the fuel system.

[0013] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a fueling value regarding a regeneration event; and responsive to determining that the fueling value is at or above a fourth predefined threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0014] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include enabling a third flag responsive to determining that the first temperature is at or below a fourth predefined threshold. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0015] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a fourth predefined threshold; and responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0016] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a regeneration event stage of a regeneration event; and responsive to the regeneration event stage being during or after a predefined regeneration stage, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0017] In some embodiments, receiving the one or more enable conditions includes receiving an indication of an amount of time that the first component of the aftertreatment system has been operating is at or below a fourth predefined threshold.

[0018] In some embodiments, receiving the one or more enable conditions includes receiving an indication that an efficiency value of the first component is at or above a predefined threshold.

[0019] In some embodiments, receiving the one or more enable conditions includes receiving a regeneration event trigger indicative of one or more conditions that trigger a regeneration event including at least one of a duration since a most recent regeneration event elapsing, a pressure value regarding a second component of the aftertreatment system being at or above a predefined pressure threshold, or a user input.

[0020] Yet another embodiment relates to a system. The system includes an aftertreatment system coupled to an engine and a controller coupled to the engine, a fuel system, and the aftertreatment system, the controller including one or more processors and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations. The operations include: receiving one or more enable conditions regarding at least one of the engine, the fuel system, or the aftertreatment system; and responsive to receiving the one or more enable conditions: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of a presence of biodiesel in the fuel system.

[0021] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a fueling value regarding a regeneration event; enabling a third flag responsive to determining that the fueling value is at or above a fourth predefined threshold; and enabling a fourth flag responsive to determining that the first temperature is at or below a fifth predefined threshold.

[0022] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a sixth predefined threshold; enabling a fifth flag responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold; receiving a regeneration event stage of a regeneration event; and enabling a sixth flag responsive to the regeneration event stage being during or after a predefined regeneration stage.

[0023] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include enabling the biodiesel detection flag responsive to enabling at least the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag.

[0024] Numerous specific details are provided to impart a thorough understanding of embodiments of the subject matter of the present disclosure. The described features of the subject matter of the present disclosure may be combined in any suitable manner in one or more embodiments and / or implementations. In this regard, one or more features of an aspect of the invention may be combined with one or more features of a different aspect of the invention. Moreover, additional features may be recognized in certain embodiments and / or implementations that may not be present in all embodiments or implementations.BRIEF DESCRIPTION

[0025] FIG. 1 is a block diagram of an engine system, according to an example embodiment. FIG. 2 is a block diagram of a controller of the system of FIG. 1, according to an example embodiment. FIG. 3 is a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4A is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4B is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 5 is an illustration of a graph depicting a temperature deficit over time, according to an example embodiment. DETAILED DESCRIPTION

[0026] Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, computer-readable media, and systems for detecting biodiesel in a fuel system of an internal combustion engine system. A fuel system may facilitate one or more functions in an engine system including, but not limited to, providing fuel to engine components, such as combustion cylinders. Before turning to the Figures, which illustrate certain exemplary embodiments in detail, it should be understood that the present disclosure is not limited to the details or methodology set forth in the description or illustrated in the Figures. It should also be understood that the terminology used herein is for the purpose of description only and should not be regarded as limiting.

[0027] As utilized herein, the term "estimating" and like terms are used to refer to determining a value based on data (e.g., sensor data, historical sensor data, real-time sensor data, etc.), which may be close but not necessarily exactly the actual value. In some embodiments, estimating a current or future value can be performed using one or more models (e.g., statistical models, artificial intelligence models, machine learning models, etc.). For example, estimating a temperature of exhaust gas can include using data, such as sensor data, with a model to determine the temperature value.

[0028] As utilized herein, the term "measuring" and like terms are used to refer to determining an approximate value based on detecting or receiving information regarding the measured value / parameter (e.g., using a sensor). The measured value may be closer to the actual value (e.g., compared to estimating the value) but not necessarily exactly the actual value of the parameter value.

[0029] As used herein, "predicting" and similar terms, in addition to the plain meaning of the words, are used to mean estimating or otherwise determining a future value or characteristic. In some embodiments, predicting the future value can be performed using one or more models (e.g., statistical models, artificial intelligence models, machine learning models, etc.). For example, predicting a temperature of exhaust gas can include using data, such as sensor data, with a model to determine the future temperature value.

[0030] As utilized herein, the term "operational data" and like terms are used to refer to data regarding the operation of a system, such as an engine system. In some embodiments, operational data may include settings, values, or other information regarding the operation of a system. In some embodiments, the operational data may be measured (e.g., by one or more real sensors) and / or estimated or determined (e.g., by one or more virtual sensors or by a computer device or processing circuit).

[0031] As described herein, an engine system may include an engine and an exhaust aftertreatment system in exhaust gas receiving communication with the engine. The engine may be an internal combustion engine (ICE) configured to combust fuel. In some embodiments, the fuel is a petrodiesel fuel. In some embodiments, the fuel is a biodiesel fuel. In some embodiments, the fuel is a blend of biodiesel and petrodiesel. During normal operation of an engine, the ICE may produce various chemicals resulting from combusting the fuel in the presence of air, such as nitrogen oxides (NOx), carbon oxides (CO, CO 2 ), sulfur oxides (SOx), particulate matter, such as ash or soot, and / or other substances resulting from the combustion of the fuel. The products of combustion may be routed out of the engine with exhaust gases and to one or more downstream components, such as an aftertreatment system.

[0032] The exhaust aftertreatment system may include one or more components, such as a particulate filter configured to remove particulate matter, such as soot, from exhaust gas flowing in the exhaust gas conduit system, a dosing module (e.g., a doser) configured to supply a dosing fluid to the exhaust gas flowing in the exhaust gas system, and one or more catalyst devices configured to facilitate conversion of the exhaust gas constituents (e.g., nitrogen oxides, NO x ) to less harmful elements (e.g., water, nitrogen), such as an oxidation catalyst, a selectively catalytic reduction (SCR) system, a three-way catalyst, and so on. A control system or controller may monitor one or more parameters of the components of the engine system using one or more sensors (e.g., actual sensors and / or virtual sensors) to collect and / or determine sensor data. The control system may analyze the sensor data and compare the analyzed sensor data with one or more thresholds.

[0033] Over time, the particulate filter may accumulate particulate matter, reducing the effectiveness of the particulate filter (e.g., reducing the ability of the particulate filter to remove particulate matter from the exhaust gas). The control system may cause a "regeneration event" whereby a temperature of the exhaust gas (e.g., the exhaust gas temperature) increases to at or above a predetermined threshold. When the exhaust gas temperature is at or above the predetermined threshold, at least a portion of the particulate matter accumulated on the particulate filter is burnt off, reducing the amount of particulate matter on the particulate filter.

[0034] In some embodiments, the regeneration event includes causing a predetermined amount of fuel (e.g., biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel) to enter the exhaust aftertreatment system. The oxidation catalyst may facilitate oxidation of the fuel. The oxidation of the fuel is an exothermic reaction that increases the temperature of the exhaust gas. However, when the fuel is or includes biodiesel, the increase in temperature resulting from the oxidation of the fuel may be below the predetermined threshold temperature for the regeneration event. In some embodiments, when the exhaust gas temperature is below the predetermined threshold, the particulate matter accumulated on the particulate filter does not burn off, and the amount of particulate matter accumulated on the particulate filter may increase or remain substantially constant.

[0035] Advantageously and as described herein, the control system or controller may implement one or more controls to detect the presence of biodiesel in the fuel. As described herein, the control system may, responsive to detecting the presence of biodiesel in the fuel, implement one or more controls to adjust the regeneration event to account for the presence of biodiesel in the fuel, such as, for example, increasing the predetermined amount of fuel provided to the aftertreatment system, increasing a frequency of regeneration events (e.g., decreasing the time between regeneration events), providing one or more notifications to a user, such as a mechanic, operator of the engine system, or other suitable user, indicating the presence of biodiesel in the fuel and / or a recommendation to service or replace the particulate filter, and so on.

[0036] Technically and beneficially, the systems, methods, and apparatuses described herein provide an improved control system that enables the control system to determine the presence of biodiesel in the fuel without directly measuring or sensing the chemical composition of the fuel. The control system described herein advantageously utilizes a particular control strategy to identify the presence of biodiesel in the fuel using one or more sensors positioned in the aftertreatment system, such as one or more temperature sensors. That is, the systems and methods described herein provide a technical solution to the technical problem of identifying the presence of biodiesel in fuel, without directly determining the chemical composition of the fuel and / or without the use of specialized sensors configured to sense or detect the chemical composition of the fuel. Advantageously, the presence of biodiesel in fuel is determined using one or more sensors that are typically included in an aftertreatment system, such as, for example, temperature sensors.

[0037] Now referring to FIG. 1, a schematic view of a block diagram of a system 100 (e.g., an engine system) is shown, according to an example embodiment. The system 100 includes an engine 101, an aftertreatment system 120 in exhaust gas receiving communication with the engine 101. The system 100 may also include a controller 140 (as shown in FIG. 2) and an operator input / output (I / O) device 130 (as shown in FIG. 2), where the controller 140 is communicably coupled to each of the aforementioned components. In the configuration of FIG. 1, the system 100 is included in a vehicle. The vehicle may be any type of on-road or off-road vehicle including, but not limited to, wheel-loaders, fork-lift trucks, line-haul trucks, mid-range trucks (e.g., pick-up trucks, etc.), sedans, coupes, tanks, airplanes, boats, and any other type of vehicle. In another embodiment, the system 100 may be embodied in a stationary piece of equipment, such as a power generator or genset. All such variations are intended to fall within the scope of the present disclosure.

[0038] The engine 101 may be any type of internal combustion engine that generates exhaust gas. In the example depicted, the engine 101 is a part of a diesel engine system. The engine 101 is configured to combust a diesel fuel including biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel. In some embodiments, the engine 101 is part of a hybrid engine system having a combination of an internal combustion engine and at least one electric motor coupled to at least one battery. In some embodiments, the hybrid engine system may be configured as a mild-hybrid powertrain, a parallel hybrid powertrain, a series hybrid powertrain, or a series-parallel powertrain.

[0039] As shown in FIG. 1, an intake air throttle (IAT) valve 102, a fuel system 103, and an oil system 104 are coupled to the engine 101. The IAT valve 102 is structured to control an amount of air supplied to the engine 101. The fuel system 103 is structured to provide fuel (e.g., biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel) to the engine 101 (e.g., from a fuel source). The fuel system 103 may control one or more fueling parameters including a fuel amount, a fuel pressure, a fuel injection timing, etc. In some embodiments, the fuel system 103 is or includes a fuel storage device, such as a storage tank. The fuel storage device is configured to store the fuel. In some embodiments, the system 100 may receive the fuel via the fuel system 103 (e.g., at the fuel storage device). The oil system 104 is configured to provide lubricant (e.g., lubricant oil) to the engine 101.

[0040] The IAT valve 102 is a valve positioned at an air inlet of the engine 101. The IAT valve 102 may be actuated (e.g., by an actuator controlled by the controller 140) between an open position and a closed position. In the open position, the IAT valve 102 allows a maximum amount of air to flow from the air intake to the engine 101. In the closed position, the IAT valve 102 allows a minimum amount of air to flow from the air intake to the engine 101. The controller 140 may selectively actuate the IAT valve 102 (e.g., by controlling the actuator) in a plurality of positions between and / or including the open position and the closed position to adjust the amount of air received by the engine 101.

[0041] The aftertreatment system 120 is in exhaust-gas receiving communication with the engine 101. In the example depicted, the aftertreatment system includes a diesel oxidation catalyst (DOC) 121, a diesel particulate filter (DPF) 122, and a selective catalytic reduction (SCR) system 123. In some embodiments, the aftertreatment system 120 includes an ammonia slip catalyst (ASC) 128. The DOC 121, the DPF 122, the SCR 123, and the ASC 128 may be fluidly coupled by an exhaust gas conduit. The DOC 121 is structured to receive the exhaust gas from the engine 101 and to oxidize one or more exhaust gas constituents (e.g., fuel, hydrocarbons, etc.) in the exhaust gas. The DPF 122 is arranged or positioned downstream of the DOC 121 and structured to remove particulates or particulate matter, such as soot, from exhaust gas flowing in the exhaust gas stream. The DPF 122 includes an inlet, where the exhaust gas is received, and an outlet, where the exhaust gas exits after having particulate matter substantially filtered from the exhaust gas. In some implementations, the DPF 122 or other components may be omitted and / or other components added (e.g., a second SCR system having an additional dosing unit or module, multiple DOCs, etc.). Additionally, although a particular arrangement is shown for the aftertreatment system 120 in FIG. 1, the arrangement of components within the aftertreatment system 120 may be different in other embodiments (e.g., the DPF 122 positioned downstream of the SCR 123 and ASC).

[0042] The aftertreatment system 120 may further include a reductant delivery system which may include a decomposition chamber (e.g., decomposition reactor, reactor pipe, decomposition tube, reactor tube, etc.) to convert a reductant into ammonia, shown as a dosing module or unit 124. The reductant may be, for example, urea, diesel exhaust fluid (DEF), Adblue ®< , a urea water solution (UWS), an aqueous urea solution (e.g., AUS32, etc.), and other similar fluids. The dosing module 124 may include a reservoir, a pump, and a nozzle (and potentially other components or devices). The reservoir may be structured to store the reductant. The pump may be fluidly coupled to the reservoir and the nozzle by a dosing conduit and structured to pump the reductant from the reservoir to the nozzle. The nozzle may provide the reductant to the exhaust gas within the exhaust gas conduit. The reductant fluid is added to the exhaust gas stream to aid in the catalytic reduction. As shown in FIG. 1, the reductant may be injected upstream of the SCR 123 generally (or in particular, the SCR catalyst) by the dosing module 124 such that the SCR catalyst receives a mixture of the reductant and exhaust gas. The reductant droplets then undergo the processes of evaporation, thermolysis, and hydrolysis to form gaseous ammonia within the decomposition chamber, the SCR catalyst, and / or the exhaust gas conduit system, which leaves the aftertreatment system 120.

[0043] As indicated above, the aftertreatment system 120 may further include an oxidation catalyst (e.g., the DOC 121) fluidly coupled to the exhaust gas conduit system to oxidize one or more gas constituents (e.g., hydrocarbons, carbon monoxide, etc.) of the exhaust gas. In order to properly assist in this reduction, the DOC 121 may be required to be at a certain operating temperature. In some embodiments, this certain operating temperature is approximately between 200-500 °C. In other embodiments, the certain operating temperature is the temperature at which the conversion efficiency of the DOC 121 exceeds a predefined threshold (e.g., the conversion of HC to less harmful compounds, which is known as the HC conversion efficiency).

[0044] In some embodiments, the DOC 121 is configured to facilitate the oxidation of fuel (e.g., biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel) in the aftertreatment system 120. The oxidation of fuel is an exothermic reaction that increases the temperature of the exhaust gas. Advantageously, when the DOC 121 facilitates the oxidation of the fuel, the temperature of the exhaust gas may increase, thereby increasing the temperature of one or more components of the aftertreatment system 120 downstream of the DOC 121, such as the DPF 122. In various embodiments, the change in temperature of the exhaust gas between an inlet of the DOC 121 and an outlet of the DOC 121 is referred to herein as the "exotherm" of the DOC 121.

[0045] The SCR 123 is configured to assist in the reduction of NO x emissions by accelerating a NOx reduction process between the ammonia and the NO x of the exhaust gas into diatomic nitrogen (N 2 ) and water (H 2 O). If the SCR catalyst is not at or above a certain temperature, the acceleration of the NOx reduction process is limited and the SCR 123 may not be operating at a level of a desired conversion efficiency (i.e., a value indicative of an amount of reduction of NO x emissions, also referred to as "deNO x efficiency"). In some embodiments, this certain temperature is approximately 200-600 °C. The SCR catalyst may be made from a combination of an inactive material and an active catalyst, such that the inactive material (e.g., ceramic substrate) directs the exhaust gas towards the active catalyst, which is any sort of material suitable for catalytic reduction (e.g. metal exchanged zeolite (Fe or Cu / zeolite), base metals oxides like vanadium, molybdenum, tungsten, etc.).

[0046] When ammonia in the exhaust gas does not react with the SCR catalyst (either because the SCR 123 is below operating temperature or because the amount of dosed ammonia greatly exceeds the amount of NO x ), the unreacted ammonia may bind to the SCR catalyst, becoming stored in the SCR 123. This stored ammonia is released from the SCR 123 as the SCR 123 warms, which can cause issues if the amount of ammonia released is greater than the amount of NO x passing through (i.e., more ammonia than needed for the amount of NO x , which can lead to ammonia slip). In some embodiments, the ASC is included and structured to address ammonia slip by removing at least some excess ammonia from the treated exhaust gas before the treated exhaust gas is released into the atmosphere. As exhaust gas passes through the ASC, some of unreacted ammonia (i.e., unreacted with NOx) remaining in the exhaust gas is partially oxidized to NOx, which then consequently reacts with the remaining unreacted ammonia to form N2 gas and water. However, similar to the SCR catalyst, if the ASC is not at or above a certain temperature, the acceleration of the NH3 reduction process is limited and the ASC may not be operating at a level of efficiency to meet regulations or desired parameters. In some embodiments, this certain temperature is approximately 250-300°C.

[0047] As shown, a plurality of sensors 125 are included in the aftertreatment system 120. The number, placement, and type of sensors included in the aftertreatment system 120 are shown for example purposes only. That is, in other configurations, the number, placement, and type of sensors may differ. The sensors 125 may be gas constituent sensors (e.g., NO x sensors, oxygen sensors, etc.), temperature sensors, particulate matter (PM) sensors, flow rate sensors (e.g., mass flow rate sensors, volumetric flow rate sensors, etc.), other exhaust gas emissions constituent sensors, pressure sensors, some combination thereof, and so on. The gas constituent sensors may include an oxygen sensor that is structured to acquire data indicative of the presence of oxygen in the exhaust gas. The data from the oxygen sensor may be used to estimate an air-to-fuel ratio (AFR) value. The flow rate sensors may include a mass air flow (MAF) sensor structured to acquire data indicative of a mass flow rate of the exhaust gas. The temperature sensors are structured to acquire data indicative of a temperature value at each location where the temperature sensor is located.

[0048] The sensors 125 may be located in or proximate the engine 101, after the engine 101 and before the aftertreatment system 120, after the aftertreatment system 120, in the aftertreatment system as shown (e.g., upstream and / or downstream of the DOC 121, the DPF 122, and / or the SCR 123, etc.), upstream of the engine 101, etc. It should be understood that the location of the sensors may vary. In one embodiment, there may be sensors 125 located both before and after the aftertreatment system 120. In one embodiment, at least one of the sensors is structured as exhaust gas constituent sensors (e.g., CO, NOx, PM, SOx, etc. sensors). In another embodiment, at least one of the sensors 125 is structured as non-exhaust gas constituent sensors that are used to estimate exhaust gas emissions (e.g., temperature, flowrate, pressure, etc.). Additional sensors may be also included with the system 100. The sensors may include engine-related sensors (e.g., torque sensors, speed sensors, pressure sensors, flowrate sensors, temperature sensors, etc.). For example, in some embodiments, at least one of the sensors 125 is structured as an oil temperature sensor that is used to detect and / or determine an engine oil temperature. The sensors may further include sensors associated with other components of the vehicle (e.g., speed sensor of a turbo charger, fuel quantity and injection rate sensor, fuel rail pressure sensor, etc.).

[0049] The sensors 125 may be real or virtual (i.e., a non-physical sensor that is structured as program logic in the controller 140 that makes various estimations or determinations). For example, an engine speed sensor may be a real or virtual sensor arranged to measure or otherwise acquire data, values, or information indicative of a speed of the engine 101 (typically expressed in revolutions-per-minute). The sensor is coupled to the engine (when structured as a real sensor) and is structured to send a signal to the controller 140 indicative of the speed of the engine 101. When structured as a virtual sensor, at least one input may be used by the controller 140 in an algorithm, model, lookup table, etc. to determine or estimate a parameter of the engine (e.g., power output, etc.). Any of the sensors 125 described herein may be real or virtual.

[0050] The controller 140 is coupled to and, in particular, communicably coupled, to the sensors 125. Accordingly, the controller 140 is structured to receive data from one or more of the sensors 125 and provide instructions / information to the one or more sensors 125. The received data may be used by the controller 140 to control one or more components in the system 100 and / or for monitoring and thermal management purposes.

[0051] The operator input / output (I / O) device 130 may be coupled to the controller 140, such that information may be exchanged between the controller 140 and the I / O device 130, where the information may relate to one or more components of FIG. 1 or determinations (described below) of the controller 140. The operator I / O device 130 enables an operator of the system 100 to communicate with the controller 140 and one or more components of the system 100 of FIG. 1. For example, the operator input / output device 130 may include, but is not limited to, an interactive display, a touchscreen device, one or more buttons and switches, voice command receivers, etc. In this way, the operator input / output device 130 may provide one or more indications or notifications to an operator, such as a malfunction indicator lamp (MIL), etc. Additionally, the vehicle may include a port that enables the controller 140 to connect or couple to a scan tool so that fault codes and other information regarding the vehicle may be obtained.

[0052] The controller 140 is structured to control, at least partly, the operation of the system 100 and associated sub-systems, such as the engine 101 and the operator I / O device 130. Communication between and among the components may be via any number of wired or wireless connections. For example, a wired connection may include a serial cable, a fiber optic cable, a CAT5 cable, or any other form of wired connection. In comparison, a wireless connection may include the Internet, Wi-Fi, cellular, radio, etc. In one embodiment, a controller area network (CAN) bus provides the exchange of signals, information, and / or data. The CAN bus includes any number of wired and wireless connections. Because the controller 140 is communicably coupled to the systems and components of FIG. 1, the controller 140 is structured to receive data from one or more of the components shown in FIG. 1. The structure and function of the controller 140 is further described in regard to FIG. 2.

[0053] As the components of FIG. 1 are shown to be embodied in the system 100, the controller 140 may be structured as one or more electronic control units (ECUs), such as one or more microcontrollers. The controller 140 may be separate from or included with at least one of a transmission control unit, an exhaust aftertreatment control unit, a powertrain control module, an engine control module, etc.

[0054] Now referring to FIG. 2, a schematic diagram of the controller 140 of the system 100 of FIG. 1 is shown, according to an example embodiment. As shown, the controller 140 includes at least one processing circuit 202 having at least one processor 204 and at least one memory device 206, a biodiesel detection circuit 212, and a communications interface 216. The controller 140 is structured to monitor the engine 101 and the aftertreatment system 120 to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103) based on, for example, monitoring the engine and / or the aftertreatment system 120.

[0055] In one configuration, the biodiesel detection circuit 212 is embodied as machine or computer-readable media storing instructions that are executable by a processor, such as processor 204. As described herein and amongst other uses, the machine-readable media facilitates performance of certain operations to enable reception and transmission of data. For example, the machine-readable media may provide an instruction (e.g., command, etc.) to, e.g., acquire data. In this regard, the machine-readable media may include programmable logic that defines the frequency of acquisition of the data (or, transmission of the data). The computer readable media instructions may include code, which may be written in any programming language including, but not limited to, Java or the like and any conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may be executed on one processor or multiple remote processors. In the latter scenario, the remote processors may be connected to each other through any type of network (e.g., CAN bus, etc.).

[0056] In another configuration, biodiesel detection circuit 212 is embodied as one or more hardware units, such as one or more electronic control units. As such, biodiesel detection circuit 212 may be embodied as one or more circuitry components including, but not limited to, processing circuitry, network interfaces, peripheral devices, input devices, output devices, sensors, etc. In some embodiments, the biodiesel detection circuit 212 may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (IC), discrete circuits, system on a chip (SOCs) circuits, microcontrollers, etc.), telecommunication circuits, hybrid circuits, and any other type of "circuit." In this regard, biodiesel detection circuit 212 may include any type of component for accomplishing or facilitating the achievement of the operations described herein. For example, a circuit as described herein may include one or more transistors, logic gates (e.g., NAND, AND, NOR, OR, XOR, NOT, XNOR, etc.), resistors, multiplexers, registers, capacitors, inductors, diodes, wiring, and so on. The biodiesel detection circuit 212 may also include or be programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like. The biodiesel detection circuit 212 may include one or more memory devices for storing instructions that are executable by the processor(s) of the biodiesel detection circuit 212. The one or more memory devices and processor(s) may have the same definition as provided below with respect to the memory device 206 and processor 204. In some hardware unit configurations, the biodiesel detection circuit 212 may be geographically dispersed throughout separate locations in the vehicle. Alternatively and as shown, the biodiesel detection circuit 212 may be embodied in or within a single unit / housing, which is shown as the controller 140.

[0057] In the example shown, the controller 140 includes the processing circuit 202 having the processor 204 and the memory device 206. The processing circuit 202 may be structured or configured to execute or implement the instructions, commands, and / or control processes described herein with respect to the biodiesel detection circuit 212. The depicted configuration represents the biodiesel detection circuit 212 being embodied as machine or computer-readable media storing instructions. However, as mentioned above, this illustration is not meant to be limiting as the present disclosure contemplates other embodiments where the biodiesel detection circuit 212 is configured as a hardware unit. All such combinations and variations are intended to fall within the scope of the present disclosure.

[0058] The processor 204 may be implemented as one or more single- or multi-chip processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), and / or suitable processors (e.g., other programmable logic devices, discrete hardware components, etc. to perform the functions described herein). A processor may be a microprocessor, a group of processors, etc. A processor also may be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some embodiments, the one or more processors may be shared by multiple circuits (e.g., the biodiesel detection circuit 212 may comprise or otherwise share the same processor which, in some example embodiments, may execute instructions stored, or otherwise accessed, via different areas of memory). Alternatively or additionally, the one or more processors may be structured to perform or otherwise execute certain operations independent of one or more co-processors. In other example embodiments, two or more processors may be coupled via a bus to enable independent, parallel, pipelined, or multi-threaded instruction execution. All such variations are intended to fall within the scope of the present disclosure.

[0059] The memory device 206 (e.g., memory, memory unit, storage device) may include one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage) for storing data and / or computer code for completing or facilitating the various processes, layers and modules described in the present disclosure. For example, the memory device 206 may include dynamic random-access memory (DRAM). The memory device 206 may be communicably connected to the processor 204 to provide computer code or instructions to the processor 204 for executing at least some of the processes described herein. Moreover, the memory device 206 may be or include tangible, non-transient volatile memory or non-volatile memory. Accordingly, the memory device 206 may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein.

[0060] The communications interface 216 may include any combination of wired and / or wireless interfaces (e.g., jacks, antennas, transmitters, receivers, transceivers, wire terminals) for conducting data communications with various systems, devices, or networks structured to enable in-vehicle communications (e.g., between and among the components of the vehicle) and out-of-vehicle communications (e.g., with a remote server). For example and regarding out-of-vehicle / system communications, the communications interface 216 may include an Ethernet card and port for sending and receiving data via an Ethernet-based communications network and / or a Wi-Fi transceiver for communicating via a wireless communications network. The communications interface 216 may be structured to communicate via local area networks or wide area networks (e.g., the Internet) and may use a variety of communications protocols (e.g., IP, LON, Bluetooth, ZigBee, radio, cellular, near field communication).

[0061] In various embodiments, the controller 140 and / or one or more components thereof, such as the biodiesel detection circuit 212, is configured to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103). Advantageously, the controller 140 is configured to determine the presence of biodiesel in the system 100 without directly measuring or sensing the chemical composition of fuel stored in the system 100.

[0062] In some embodiments, the controller 140 is configured to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103) responsive to receiving one or more enable conditions. As described herein, an "enable condition" refers to a predefined operating condition of the system 100. The enable condition may be received or determined by the controller 140 based on a control signal or other information received by the controller 140, such as a predefined condition detected by one or more sensors 125.

[0063] In some embodiments, the enable condition includes receiving a regeneration event trigger. The regeneration event trigger is or is indicative of a condition or plurality of conditions that triggers a regeneration event. The regeneration event trigger may be a predefined duration (e.g., an amount of time or a distance traveled by the system 100) since a most recent regeneration event elapsing (e.g., based on the controller 140 initiating a timer to track the time since a last regeneration event or a location of the system 100), a detected or determined pressure value (e.g., a pressure change) being at or above a predefined threshold across one or more components of the aftertreatment system 120 (e.g., the DOC 121, the DPF 122, etc.), and / or a user input received via an input / output device of the system.

[0064] In some embodiments, the enable condition includes an engine fault value. In one embodiment, the enable condition is based on the engine fault value indicating that a number of engine faults that are active is at or below a predefined threshold. In another embodiment, the engine fault value is based on the content associated with the active, if any, faults or fault codes. In yet another embodiment, the enable condition comprising the engine fault value is based on a combination of the number of faults and the content of the faults. As described herein, a "fault code" refers to an onboard diagnostic code (e.g., an OBD-II code, etc.) indicative of a status or characteristic of one or more components of the system 100. In some embodiments, the engine fault codes may be indicative of an issue with the operation of the engine 101, such as an issue with the coolant or oil system 104 (e.g., a coolant temperature at or below a predefined threshold, a coolant amount at or below a predefined threshold), an issue with the fuel system 103 (e.g., an AFR above a predefined threshold, an AFR below a predefined threshold, etc.), an issue with one or more cylinders of the engine 101 (e.g., one or more cylinders misfiring), and so on. In situations where no fault codes corresponding to the engine 101 are active, the engine fault may include an indication that no fault codes corresponding to the engine 101 are active.

[0065] In some embodiments, the enable condition includes an aftertreatment system sensor fault value. In one embodiment, the enable condition is based on the aftertreatment system sensor fault value indicating that a number of aftertreatment system sensor faults that are active is at or below a predefined threshold. In another embodiment, the aftertreatment system sensor fault value is based on the content associated with the active, if any, faults or fault codes. In yet another embodiment, the enable condition comprising the aftertreatment system sensor fault value is based on a combination of the number of faults and the content of the faults. In some embodiments, the fault codes corresponding to one or more sensors 125 associated with the aftertreatment system 120 may indicate, for example, an issue with a sensor, such as a sensor not reporting data, a sensor reporting data outside a predefined range or outside a predefined set of values (e.g., temperatures lower than ambient, temperatures higher than engine combustion temperatures, pressures lower than a predefined value, pressure higher than a predefined value, etc.), and / or other issues related to the one or more sensors 125 associated with the aftertreatment system 120. In situations where no fault codes corresponding to the one or more sensors 125 associated with the aftertreatment system 120 are active, the aftertreatment system sensor fault may include an indication that no fault codes corresponding to the one or more sensors 125 associated with the aftertreatment system 120 are active.

[0066] In some embodiments, the enable condition includes a system fault value. In one embodiment, the enable condition is based on the system fault value indicating that a number of system faults that are active is at or below a predefined threshold. In another embodiment, the system fault value is based on the content associated with the active, if any, faults or fault codes. In yet another embodiment, the enable condition comprising the system fault value is based on a combination of the number of faults and the content of the faults. In some embodiments, the system fault codes may be indicative of an issue with the operation of the system 100, such as an issue with the engine 101, the aftertreatment system 120 (e.g., a conversion rate of NOx at or below a predefined value, etc.), and so on. In situations where no fault codes corresponding to the system 100 are active, the engine fault may include an indication that no fault codes corresponding to the system 100 are active.

[0067] In some embodiments, the enable condition includes an indication regarding an amount of time a component(s) or system of the aftertreatment system, such as the DOC 121, has been operating at or below a predefined time threshold. The amount of time the component (e.g., DOC 121) has been operating may be measured from a time when the component (e.g., DOC 121) was first installed in the aftertreatment system 120. In another embodiment, the time may only correspond to when the engine 101 is operating (e.g., combusting fuel) and not from an installation date as that installation date may include large periods of inactivity. The amount of time the component (e.g., DOC 121) has been operating may be tracked in a variety of units (e.g., hours, days, etc.). The controller 140 may receive or determine the enable condition responsive to the amount of time the component (e.g., DOC 121) has been operating being at or below a predefined threshold.

[0068] In some embodiments, the enable condition is based on an efficiency of one or more components or systems. For example, the controller 140 may track, receive, and / or determine an efficiency value of the DOC 121. When the efficiency of the DOC 121 is at or above a predefined threshold, the controller 140 determines the enable condition is present. The efficiency value of the DOC 121 is based on an amount of fuel oxidized by the DOC 121 relative to an amount of fuel provided to the aftertreatment system 120. For example, the efficiency value of the DOC 121 may be a ratio of the amount of fuel oxidized by the DOC 121 to the amount of fuel provided to the aftertreatment system 120, expressed as a percentage. The amount of fuel provided to the aftertreatment system 120 is a predefined value. For example, the amount of fuel provided to the aftertreatment system 120 can be based on a control signal request the amount of fuel be provided to the aftertreatment system 120 or another predetermined value. The amount of fuel oxidized by the DOC 121 is based on a measured value. In one embodiment, the measured value is an amount of fuel detected downstream of the DOC 121, and the amount of fuel oxidized by the DOC 121 is the amount of fuel be provided to the aftertreatment system 120 minus the amount of fuel detected downstream of the DOC 121. In another embodiment, the measured value is a temperature value regarding the DOC 121, and the amount of fuel oxidized by the DOC 121 is determined based on, e.g., a lookup table that correlates the temperature value regarding the DOC 121 with the amount of fuel oxidized by the DOC 121. Thus, when all of the fuel provided to the aftertreatment system 120 is oxidized by the DOC 121, the efficiency value of the DOC 121 is 100%, and when half of the fuel provided to the aftertreatment system 120 is oxidized by the DOC 121, the efficiency value of the DOC 121 is 50%. In some embodiments, when the DOC 121 oxidizes less than 100% of the fuel provided to the aftertreatment system 120 at least a portion of the unoxidized fuel is provided to the DPF 122, and the DPF 122 facilitates oxidation of the fuel. In some embodiments, the predefined threshold is 80%.

[0069] In some embodiments, the enable condition includes one or more of the conditions described above and herein. For example, the enable condition may include each of the aforementioned conditions. In another example, the enable condition may include only one or a subset of the aforementioned conditions.

[0070] In some embodiments, responsive to receiving the enable condition, the controller 140 is configured to selectively determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103).

[0071] In one embodiment, the presence of biodiesel in the system 100 (e.g., in the fuel system 103) may be determined based on receiving information regarding the operation of the aftertreatment system 120. The controller 140 may receive one or more "flags" indicative of the operation of the aftertreatment system 120. As described herein, a "flag" refers to a computer-based indication of an operating characteristic of the system 100. In some embodiments a flag may be a binary indication (e.g., indicating true or false), a numeric value, such as a string value or a float value, or other indication. The flag may be stored in the memory of the controller 140. For example, a flag may indicate whether a particular operational data value regarding the operation of the system 100 does not satisfy a corresponding threshold (e.g., at or above a maximum threshold, at or below a minimum threshold, etc.). In some embodiments, the controller 140 is configured to count a number of times a particular flag (e.g., a first flag) has occurred within a predetermined time period. In these embodiments, another flag (e.g., a second flag) may be used to indicate whether a number of times that the first flag occurred is at or above a predefined threshold. A flag may be enabled or activated responsive to one or more predetermined conditions. A flag may be disabled or deactivated responsive to one or more different predetermined conditions, or a flag may be disabled or deactivated by default. In any of the above-described embodiments, the controller 140 may use multiple flags (e.g., more than one) to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103). Advantageously, the use of more than one flag may mitigate the risk of errant results, such as false positives (e.g., determining that biodiesel is present in the fuel system 103 when biodiesel is not present) and / or false negatives (e.g., determining that biodiesel is not present in the fuel system 103 when biodiesel is present).

[0072] In some embodiments, a first flag is activated based on a rate of change of a duration of a regeneration event. The "duration" of the regeneration event may be determined and / or measured by a counter that increments or counts during a "healthy" regeneration event. A regeneration event is "healthy" when one or more operating conditions of the aftertreatment system 120 are satisfied, such as one or more temperatures of the aftertreatment system 120, a component thereof, or a gas flowing therethrough, being at or above a predetermined temperature threshold. For example, the controller 140 may receive a first temperature regarding a first component of the aftertreatment system 120, such as the DOC 121. The first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may compare the first temperature regarding the DOC 121 to a predefined threshold. In some embodiments, the predefined threshold is between 200 °C and 500 °C (e.g., 300 °C). Responsive to determining that the first temperature regarding the DOC 121 is at or above the predefined threshold, the controller 140 may determine that the regeneration event is healthy. In another example, the controller 140 may determine that the regeneration event is "healthy" based on another operational characteristic of the aftertreatment system, such as a pressure value regarding the DOC 121 or the DPF 122. Accordingly, the "duration of a regeneration event" is based on a period of time during which, the temperature value of the exhaust gas and / or a component / system within in the aftertreatment system 120 is at or above the predefined threshold and a pressure value regarding one or more components of the aftertreatment system 120 (e.g., the DOC 121, the DPF 122, etc.) is at or above a predefined threshold. When these conditions are met, the controller 140 may track and / or determine the duration of the regeneration event (e.g., by incrementing the counter or counter parameter). The counter parameter is held constant (e.g., is not incremented) when the regeneration is not healthy (e.g., when one or temperature values regarding the aftertreatment system 120 is below a corresponding threshold, when one or more pressure values regarding the aftertreatment system 120 is below a corresponding threshold, etc.). The rate of change of the regeneration event duration is then based on a change in the regeneration event duration (e.g., the counter parameter value) over a predefined time period, such as one day, one week, one month, etc., for a single regeneration event. The controller 140 may receive or determine the rate of change of the regeneration event duration. The controller 140 may compare the rate of change of the regeneration event duration to a predefined threshold (e.g., a value between 0 and 1, inclusive, such as 0). Responsive to the rate of change of the regeneration event duration being above the predefined threshold (e.g., when the rate of change of the duration of a regeneration is greater than zero), the controller 140 may enable the first flag. Responsive to the rate of change of the regeneration event duration being at or below the predefined threshold (e.g., when the rate of change of the duration of a regeneration is at or below zero), controller 140 does not enable the first flag.

[0073] In some embodiments, a second flag is activated based on an inlet temperature of an aftertreatment system and, namely, the DOC 121. The controller 140 may receive the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may compare the first temperature regarding the DOC 121 to a predefined threshold. In some embodiments, the predefined threshold is between 300 °C and 700 °C (e.g., 500 °C). Responsive to the DOC inlet temperature being at or below the predefined threshold, the controller 140 may enable the second flag.

[0074] In some embodiments, a third flag is activated based on an a fueling value (e.g., fueling rate, a fueling amount, etc.) during a regeneration event, referred to herein as a regeneration fueling value. More specifically, the regeneration fueling value is an amount of fuel provided to the aftertreatment system 120 during a regeneration. The fuel provided to the aftertreatment system 120 is oxidized (e.g., at the DOC 121) in an exothermic reaction, thereby increasing the temperature of the exhaust in the aftertreatment system 120. The controller 140 may receive a fueling value associated with a regeneration event. The fueling value may be a flow rate (e.g., a mass flow rate, a volumetric flow rate, etc.) of fuel provided to the aftertreatment system 120 during a regeneration event. For example, the fueling value may be measured in grams of fuel per second (g / s). The controller 140 may compare the fueling value to a predefined threshold. In some embodiments, the predefined threshold is between 0.25 g / s and 1 g / s (e.g., 0 / 5 g / s). Responsive to the fueling value being at or above the predefined threshold, the controller 140 may enable the third flag.

[0075] In some embodiments, a fourth flag is activated based on a regeneration stage. In various embodiments, the regeneration event may include one or more stages, such as a first stage, a second stage, a third stage, and so on. In an example embodiment, the regeneration event includes five stages. Each stage corresponds to one of a target temperature value or a target temperature ramp rate (e.g., a change in temperature per unit time. The first stage corresponds to a first target temperature value, such as approximately 350 °C. The regeneration event is in the first stage when at least one temperature value regarding the aftertreatment system 120, a component thereof, or a gas flowing therethrough, is at or above the first target temperature value. The second stage corresponds to a first target temperature ramp rate. The regeneration event is in the second stage when the controller 140 sends a command to one or more components of the system 100, such as the engine 101, to increase the at least one temperature value regarding the aftertreatment system 120 at or above the first target temperature ramp rate. The third stage corresponds to a second target temperature value, such as approximately 500 °C. The regeneration event is in the third stage when the at least one temperature value regarding the aftertreatment system 120 is at or above the second target temperature value. The fourth stage corresponds to a second target temperature ramp rate. The regeneration event is in the fourth stage when the controller 140 sends a command to one or more components of the system 100, such as the engine 101, to increase the at least one temperature value regarding the aftertreatment system 120 at or above the second target temperature ramp rate. The fifth stage corresponds to a third target temperature value, such as approximately 600 °C. The regeneration event is in the fifth stage when the at least one temperature value regarding the aftertreatment system 120 is at or above the third target temperature value.

[0076] The controller 140 may receive information regarding the regeneration event stage, such as a current regeneration event stage. The controller 140 may compare the current regeneration event stage to a predefined threshold. In some embodiments, the predefined threshold is one of the stages of the regeneration event, such as a fifth stage. Responsive to the current stage of the regeneration event being during or after the predefined threshold stage (e.g., during or after the fifth stage), the controller 140 may enable the fourth flag.

[0077] In some embodiments, a fifth flag is activated based on a number of occurrences that an exotherm value (e.g., a DOC exotherm value) is at or below a predefined threshold for a predefined duration. The controller 140 may receive the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may receive a second temperature regarding a first component of the aftertreatment system 120, such as the DOC 121. The second temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an outlet of the DOC 121 (e.g., a DOC outlet temperature). In some embodiments, the controller 140 may receive the second temperature from one or more sensors 125 positioned downstream of the DOC 121. The controller 140 may determine the exotherm of the DOC 121 based on the first temperature and the second temperature. As described above the exotherm of the DOC 121 is the change in temperature of the exhaust gas between the inlet of the DOC 121 and the outlet of the DOC 121. The controller 140 may compare the exotherm of the DOC 121 to a predefined threshold. The controller 140 may iteratively determine the exotherm of the DOC 121 and compare the exotherm of the DOC 121 to the predefined threshold for a predefined duration. Responsive to determining that the exotherm of the DOC 121 is at or below the predefined threshold during the predefined duration, the controller 140 may increment a counter (e.g., by increasing a counter value by one). The controller 140 may compare the counter value to a predefined counter threshold. Responsive to the counter value being at or above the predefined counter threshold, the controller 140 may enable the fifth flag.

[0078] In some embodiments, a sixth flag is activated based on a comparison between an expected exotherm of the DOC 121 and the determined exotherm of the DOC 121. The controller 140 may receive the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may receive an expected temperature regarding the outlet of the DOC 121 (e.g., an expected DOC outlet temperature). The expected DOC outlet temperature occurs at a future time and / or future operation of the system 100 and is based on the operation of the system 100. In some embodiments, the expected DOC outlet temperature is determined using one or more of a lookup table and / or a model (e.g., a statical model, a physics model, a machine learning model, etc.) that correlates one or more operating conditions of the engine 101, such as an air-to-fuel ratio, a combustion temperature, an engine speed, an engine load, and so on, with the expected DOC outlet temperature. The controller 140 may determine the expected exotherm of the DOC 121 based on a difference between the DOC inlet temperature and the expected DOC outlet temperature. The controller 140 may determine an actual exotherm of the DOC 121. As described above, the DOC 121 may determine the exotherm of the DOC 121 based on, for example, the DOC inlet temperature and the DOC outlet temperature. The controller 140 may determine a difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121. The controller 140 may compare the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 with a predetermined threshold. Responsive to the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 being at or below the predetermined threshold, the controller 140 may enable the sixth flag. In other embodiments, the controller 140 may receive a target DOC outlet temperature (e.g., a desired DOC outlet temperature) that is used instead of the expected DOC outlet temperature.

[0079] In some embodiments, a biodiesel detection flag (e.g., a seventh flag) may be enabled by the controller 140 based on one or more of the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and / or the sixth flag being enabled. For example, the controller 140 may enable the seventh flag responsive to enabling the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag. Advantageously, waiting for each of the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag to be enabled before enabling the seventh flag may mitigate the risk of errant results, such as false positives (e.g., determining that biodiesel is present in the fuel system 103 when biodiesel is not present) and / or false negatives (e.g., determining that biodiesel is not present in the fuel system 103 when biodiesel is present).

[0080] In some embodiments, the controller 140 may determine a number of times the seventh flag (e.g., the biodiesel detection flag) has been enabled during a predetermined period of time and / or operation of the system. For example, the controller 140 may increment (e.g., increase by one) a counter each time the seventh flag is enabled during a predetermined period of time. In some embodiments, the controller 140 may compare a counter value (e.g., the number of times the seventh flag was enabled during the predetermined period of time) to a predetermined threshold. Responsive to determining that the counter value is at or above the predetermined threshold, the controller 140 may determine that biodiesel fuel is present in the system 100 (e.g., in the fuel system 103).

[0081] In some embodiments, responsive to determining that biodiesel fuel is present in the system 100 (e.g., in the fuel system 103), the controller 140 may generate and provide a notification indicating the presence of biodiesel in the fuel system 103. For example, the controller 140 may cause the operator I / O device to display an indication of the presence of biodiesel in the fuel system 103, such as illuminating a lamp, displaying the notification on a display, and so on. In another example, the controller 140 may provide the notification to a user device (e.g., a cellphone, a laptop, a computer, etc.) via one or more of an email message, a text message, a pop-up notification, and so on. In yet another example, the controller 140 may enable one or more fault codes indicative of biodiesel being present in the fuel system 103.

[0082] FIG. 3 is a flow diagram of a method 300 of determining the presence of biodiesel in the fuel system 103, according to an example embodiment. In particular, the controller 140 (and / or one or more components thereof) is structured to perform the method 300. In some embodiments, some of the processes of method 300 may be combined, performed in a different order, and / or omitted. In still other embodiments, additional processes may be added to the method 300 without departing from the scope of the disclosure.

[0083] At process 302, the controller 140 receives or determines a regeneration event trigger. The controller 140 may receive a first enable condition responsive to receiving the regeneration event trigger.

[0084] At process 304, the controller 140 receives an engine fault value indicating a number of engine faults that are active, the content associated with the active fault codes, or both. The controller 140 may receive a second enable condition responsive to the engine fault value being at or below the predefined threshold.

[0085] At process 306, the controller 140 receives an aftertreatment system sensor fault value indicating a number of aftertreatment system sensor faults that are active, the content associated with the active fault codes, or both. The controller 140 may receive a third enable condition responsive to the aftertreatment system sensor fault value being at or below the predefined threshold.

[0086] At process 308, the controller 140 receives a system fault value indicating that a number of system faults that are active, the content associated with the active fault codes, or both. The controller 140 may receive a fourth enable condition responsive to the system fault value being at or below the predefined threshold.

[0087] At process 310, the controller 140 receives an indication that an amount of time the DOC 121 has been operating at or below a predefined threshold. The controller 140 may receive a fifth enable condition responsive to the amount of time the DOC 121 has been operating at or below a predefined threshold.

[0088] At process 312, the controller 140 receives an indication that an efficiency value of the DOC 121 is at or above a predefined threshold. The controller 140 may receive a sixth enable condition responsive to the efficiency value of the DOC 121 being at or above the predefined threshold.

[0089] At process 314, the controller 140 executes an "exotherm logic" or exotherm process. The exotherm logic may be or include one or more processes for determining the presence of biodiesel in the fuel system 103. An example exotherm logic is shown and described herein, with respect to FIGS. 4A and 4B. In some embodiments, the controller 140 executes the exotherm logic responsive to receiving one or more enable conditions. The exotherm logic may be stored as instructions within the memory of the controller that is selectively executed by one or more processors of the controller 140. In an example embodiment, the controller 140 executes the exotherm logic responsive to receiving the first enable condition, the second enable condition, the third enable condition, the fourth enable condition, the fifth enable condition, and the sixth enable condition. In some embodiments, the controller 140 is configured to prevent execution of the exotherm logic when the controller 140 does not receive at least one of the first enable condition, the second enable condition, the third enable condition, the fourth enable condition, the fifth enable condition, or the sixth enable condition. Advantageously, by preventing execution of the exotherm logic when one or more of the enable conditions are not received, the controller 140 may mitigate errant results from the exotherm logic (e.g., false positive and / or false negative results).

[0090] At process 316, the controller 140 may provide an indication of biodiesel in the system 100 (e.g., in the fuel system 103). The controller 140 may generate and provide a notification indicating the presence of biodiesel in the system 100 (e.g., in the fuel system 103). For example, the controller 140 may cause the operator I / O device to display an indication of the presence of biodiesel in the fuel system 103, such as illuminating a lamp, displaying the notification on a display, and so on. In another example, the controller 140 may provide the notification to a user device (e.g., a cellphone, a laptop, a computer, etc.) via an email message, a text message, a pop-up notification, or other suitable notification. In yet another example, the controller 140 may enable one or more fault codes indicative of biodiesel being present in the fuel system 103.

[0091] FIGS. 4A and 4B depict a flow diagram of a method 400 of determining the presence of biodiesel in the fuel system 103, according to an example embodiment. In particular, the controller 140 is structured to perform the method 400. In some embodiments, some of the processes of method 400 may be combined, performed in a different order, and / or omitted. In still other embodiments, additional processes may be added to the method 400 without departing from the scope of the disclosure.

[0092] At process 402, The controller 140 receives or determines a first temperature regarding a first component and / or system of the aftertreatment system 120, such as the DOC 121. The first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121.

[0093] At process 404, the controller 140 compares the first temperature regarding the DOC 121 to a predefined threshold. Responsive to determining that the first temperature regarding the DOC 121 is at or above the predefined threshold, the controller 140 proceeds to process 406.

[0094] At process 406, the controller 140 receives or determines a rate of change of a regeneration event duration. At process 408, the controller 140 may compare the rate of change of the regeneration event duration to a predefined threshold. Responsive to the rate of change of the regeneration event duration being at or below the predefined threshold, the controller 140 may enable a first flag. Responsive to enabling the first flag, the controller 140 may proceed to process 450.

[0095] At process 410, the controller 140 receives or determines the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121.

[0096] At process 412, the controller 140 compares the first temperature regarding the DOC 121 to a predefined threshold. Responsive to the DOC inlet temperature being at or below the predefined threshold, the controller 140 may enable a second flag. Responsive to enabling the second flag, the controller 140 may proceed to process 450. In some embodiments, processes 410-412 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408.

[0097] At process 414, the controller 140 receives or determines a fueling rate associated with a regeneration event (e.g., the regeneration fueling value). At process 416, the controller 140 compares the fueling rate to a predefined threshold. Responsive to the fueling rate being at or above the predefined threshold, the controller 140 may enable a third flag. Responsive to enabling the third flag, the controller 140 may proceed to process 450. In some embodiments, processes 414-416 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408 and / or process 410-412.

[0098] At process 418, the controller 140 receives or determines information regarding the regeneration event stage, such as a current regeneration event stage. At process 420, the controller 140 compares the current regeneration event stage to a predefined threshold. Responsive to the current stage of the regeneration event being during or after the predefined threshold stage, the controller 140 may enable a fourth flag. Responsive to enabling the fourth flag, the controller 140 may proceed to process 450. In some embodiments, processes 418-420 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408, process 410-412, and / or processes 414-416.

[0099] At process 422, the controller receives or determines the first temperature regarding the DOC 121 (e.g., similar to process 402 and / or process 410). At process 424, the controller 140 receives a second temperature regarding a first component of the aftertreatment system 120, such as the DOC 121. The second temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an outlet of the DOC 121 (e.g., a DOC outlet temperature). In some embodiments, the controller 140 may receive the second temperature from one or more sensors 125 positioned downstream of the DOC 121.

[0100] At process 426, the controller 140 receives or determines an exotherm of the DOC 121 (e.g., an exotherm value or a DOC exotherm value) based on the first temperature and the second temperature. At process 428, the controller 140 compares the exotherm value to a predefined threshold. At process 430, the controller 140 may iteratively determine the exotherm value and compare the exotherm value to the predefined threshold during a predefined duration. Responsive to determining that the exotherm of the DOC 121 was at or below the predefined threshold during the predefined duration, the controller 140 may increment a counter (e.g., by increasing a counter value by one).

[0101] At process 432, the controller 140 compares the number of occurrences of the exotherm value being at or below the predefined threshold for the predefined duration (e.g., the counter value) to a predefined occurrences threshold. Responsive to the counter value is at or above the predefined occurrences threshold, the controller 140 may enable a fifth flag. Responsive to enabling the fifth flag, the controller 140 may proceed to process 450. In some embodiments, processes 422-432 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408, process 410-412, processes 414-416, and / or process 418-420.

[0102] At process 434, the controller 140 receives or determines the first temperature regarding the DOC 121. At process 436, the controller 140 receives an expected DOC outlet temperature. At process 438, the controller 140 determines the expected exotherm of the DOC 121 (e.g., an expected exotherm value or an expected DOC exotherm value) based on a difference between the DOC inlet temperature and the expected DOC outlet temperature.

[0103] At process 440, the controller 140 receives or determines an actual exotherm value (e.g., an actual DOC exotherm value). For example, the controller 140 may receive information regarding the first temperature and / or the second temperature. In another example, the controller 140 may determine the actual exotherm value (e.g., at process 428).

[0104] At process 442, the controller 140 may receive or determine a difference between the expected exotherm value and the actual exotherm value. At process 444, the controller 140 compares the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 with a predetermined threshold. Responsive to the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 being at or below the predetermined threshold, the controller 140 may enable a sixth flag. Responsive to enabling the sixth flag, the controller 140 may proceed to process 450. In some embodiments, processes 434-444 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408, process 410-412, processes 414-416, process 418-420, and / or process 422-432.

[0105] At process 450, the controller 140 may enable a biodiesel detection flag (e.g., a seventh flag), responsive to receiving and / or enabling one or more of the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and / or the sixth flag being enabled. In an example embodiment, the controller 140 may enable the seventh flag responsive to enabling the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag.

[0106] At process 452, the controller 140 may receive or determine a number of times the seventh flag has been enabled during a predetermined period of time. At process 454, the controller 140 may determine the presence of biodiesel in the fuel system 103, responsive to determining that the number of times the seventh flag has been enabled during a predetermined period of time is at or above a predetermined threshold. In some embodiments, after performing the method 400, the controller may proceed to process 316 of the method 300.

[0107] FIG. 5 is an illustration of a graph 500. The graph 500 depicts a temperature deficit over time. The temperature deficit is a difference between a target temperature value and an actual temperature value. More specifically, the temperature deficit depicted in the graph 500 is a temperature deficit of a component of the aftertreatment system 120, such as the DOC 121. A first curve 502 represents the temperature deficit when the fuel in the fuel system 103 includes biodiesel. A second curve 504 represents the temperature deficit when the fuel in the fuel system 103 does not include biodiesel.

[0108] During a first period of time 510, the controller 140 may receive each of the enable conditions and execute the exotherm logic. Responsive to executing the exotherm logic during the first period of time 510, the controller 140 may determine the presence of biodiesel in the fuel system 103. During a second period of time 512, the controller 140 may receive each of the enable conditions and execute the exotherm logic. Responsive to executing the exotherm logic during the second period of time 512, the controller 140 may determine the presence of biodiesel in the fuel system 103.

[0109] As utilized herein, the terms "approximately," "about," "substantially", and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims.

[0110] It should be noted that the term "exemplary" and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0111] The term "coupled" and variations thereof, as used herein, means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent or fixed) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members coupled directly to each other, with the two members coupled to each other using one or more separate intervening members, or with the two members coupled to each other using an intervening member that is integrally formed as a single unitary body with one of the two members. If "coupled" or variations thereof are modified by an additional term (e.g., directly coupled), the generic definition of "coupled" provided above is modified by the plain language meaning of the additional term (e.g., "directly coupled" means the joining of two members without any separate intervening member), resulting in a narrower definition than the generic definition of "coupled" provided above. Such coupling may be mechanical, electrical, or fluidic. For example, circuit A communicably "coupled" to circuit B may signify that the circuit A communicates directly with circuit B (i.e., no intermediary) or communicates indirectly with circuit B (e.g., through one or more intermediaries).

[0112] References herein to the positions of elements (e.g., "top," "bottom," "above," "below") are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.

[0113] While various circuits with particular functionality are shown in FIG. 2, it should be understood that the controller 140 may include any number of circuits for completing the functions described herein. For example, the activities and functionalities of the biodiesel detection circuit 212 may be combined in multiple circuits or as a single circuit. Additional circuits with additional functionality may also be included. Further, the controller 140 may further control other activity beyond the scope of the present disclosure.

[0114] As mentioned above and in one configuration, the "circuits" may be implemented in machine-readable medium for execution by one or more of various types of processors, such as the processor 204 of FIG. 3. Executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the circuit and achieve the stated purpose for the circuit. Indeed, a circuit of computer readable program code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within circuits, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network.

[0115] While the term "processor" is briefly defined above, the term "processor" and "processing circuit" are meant to be broadly interpreted. In this regard and as mentioned above, the "processor" may be implemented as one or more processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components structured to execute instructions provided by memory. The one or more processors may take the form of a single core processor, multi-core processor (e.g., a dual core processor, triple core processor, quad core processor, etc.), microprocessor, etc. In some embodiments, the one or more processors may be external to the apparatus, for example the one or more processors may be a remote processor (e.g., a cloud based processor). Alternatively or additionally, the one or more processors may be internal and / or local to the apparatus. In this regard, a given circuit or components thereof may be disposed locally (e.g., as part of a local server, a local computing system, etc.) or remotely (e.g., as part of a remote server such as a cloud based server). To that end, a "circuit" as described herein may include components that are distributed across one or more locations.

[0116] Embodiments within the scope of the present disclosure include program products comprising computer or machine-readable media for carrying or having computer or machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a computer. The computer readable medium may be a tangible computer readable storage medium storing the computer readable program code. The computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable medium may include but are not limited to a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), an optical storage device, a magnetic storage device, a holographic storage medium, a micromechanical storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, and / or store computer readable program code for use by and / or in connection with an instruction execution system, apparatus, or device. Machine-executable instructions include, for example, instructions and data which cause a computer or processing machine to perform a certain function or group of functions.

[0117] The computer readable medium may also be a computer readable signal medium. A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electrical, electro-magnetic, magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport computer readable program code for use by or in connection with an instruction execution system, apparatus, or device. Computer readable program code embodied on a computer readable signal medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, Radio Frequency (RF), or the like, or any suitable combination of the foregoing.

[0118] In one embodiment, the computer readable medium may comprise a combination of one or more computer readable storage mediums and one or more computer readable signal mediums. For example, computer readable program code may be both propagated as an electro-magnetic signal through a fiber optic cable for execution by a processor and stored on RAM storage device for execution by the processor.

[0119] Computer readable program code for carrying out operations for aspects of the present disclosure may be written in any combination of one or more other programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone computer-readable package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0120] The program code may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function / act specified in the schematic flowchart diagrams and / or schematic block diagrams block or blocks.

[0121] Although the figures and description may illustrate a specific order of method steps, the order of such steps may differ from what is depicted and described, unless specified differently above. Also, two or more steps may be performed concurrently or with partial concurrence, unless specified differently above. Such variation may depend, for example, on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations of the described methods could be accomplished with standard programming techniques with rule-based logic and other logic to accomplish the various connection steps, processing steps, comparison steps, and decision steps.

[0122] It is important to note that the construction and arrangement of the apparatus and system as shown in the various exemplary embodiments is illustrative only. Additionally, any element disclosed in one embodiment may be incorporated or utilized with any other embodiment disclosed herein.

Examples

Embodiment Construction

[0025] FIG. 1 is a block diagram of an engine system, according to an example embodiment. FIG. 2 is a block diagram of a controller of the system of FIG. 1, according to an example embodiment. FIG. 3 is a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4A is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4B is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 5 is an illustration of a graph depicting a temperature deficit over time, according to an example embodiment.

DETAILED DESCRIPTION

[0026]Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, computer-readable media, and systems for detecting biodiesel in a fuel system of an internal ...

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This Applications claims the benefit of and priority to Indian Provisional Application No. 202441068032 filed September 9, 2024, which is incorporated herein by reference in its entirety and for all purposes.FIELD

[0002] The present disclosure relates generally to systems and methods for detecting biodiesel in fuel systems.BACKGROUND

[0003] Biodiesel is a renewable biofuel derived from biological sources, such as vegetable oils, animal fats, and / or recycled greases. Biodiesel may be or include long-chain fatty acid esters. Biodiesel may be used as fuel in internal combustion engine systems. In some internal combustion engine systems, the biodiesel may include a blend of biodiesel and a hydrocarbon-based diesel, commonly referred to as a "petrodiesel." A blend of biodiesel and petrodiesel having 20% or less biodiesel can be used in conventional internal combustion engine systems, with limited modifications to the internal combustion engine systems.SUMMARY

[0004] One embodiment relates to a method of determining a presence of biodiesel in a fuel system. The method includes: receiving, by at least one processor, one or more enable conditions regarding at least one of an engine system coupled to the fuel system or an aftertreatment system coupled to the engine system; and responsive to receiving the one or more enable conditions, executing an exotherm logic by the at least one processor to perform operations including: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component, based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of the presence of biodiesel in the fuel system.

[0005] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: receiving a fueling value regarding a regeneration event; and responsive to determining that the fueling value is at or above a fourth predefined threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0006] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including enabling a third flag responsive to determining that the first temperature is at or below a fourth predefined threshold. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0007] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a fourth predefined threshold; and responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0008] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: receiving a regeneration event stage of a regeneration event; and responsive to the regeneration event stage being during or after a predefined regeneration stage, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0009] In some embodiments, receiving the one or more enable conditions includes receiving an indication of an amount of time that the first component of the aftertreatment system has been operating is at or below a fourth predefined threshold.

[0010] In some embodiments, receiving the one or more enable conditions includes receiving an indication that an efficiency value of the first component is at or above a predefined threshold.

[0011] In some embodiments, the exotherm logic is executed by the at least one processor to perform further operations including: responsive to enabling the biodiesel detection flag, incrementing a biodiesel detection counter value; and responsive to the biodiesel detection counter value being at or above a predetermined biodiesel detection counter threshold, generating the indication of the presence of biodiesel in the fuel system.

[0012] Another embodiment relates to a system. The system includes a controller coupled to an engine, a fuel system, and an aftertreatment system, the controller including one or more processors and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations. The operations include: receiving one or more enable conditions regarding at least one of the engine, the fuel system, or the aftertreatment system; and responsive to receiving the one or more enable conditions: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of a presence of biodiesel in the fuel system.

[0013] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a fueling value regarding a regeneration event; and responsive to determining that the fueling value is at or above a fourth predefined threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0014] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include enabling a third flag responsive to determining that the first temperature is at or below a fourth predefined threshold. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0015] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a fourth predefined threshold; and responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0016] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a regeneration event stage of a regeneration event; and responsive to the regeneration event stage being during or after a predefined regeneration stage, enabling a third flag. The biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

[0017] In some embodiments, receiving the one or more enable conditions includes receiving an indication of an amount of time that the first component of the aftertreatment system has been operating is at or below a fourth predefined threshold.

[0018] In some embodiments, receiving the one or more enable conditions includes receiving an indication that an efficiency value of the first component is at or above a predefined threshold.

[0019] In some embodiments, receiving the one or more enable conditions includes receiving a regeneration event trigger indicative of one or more conditions that trigger a regeneration event including at least one of a duration since a most recent regeneration event elapsing, a pressure value regarding a second component of the aftertreatment system being at or above a predefined pressure threshold, or a user input.

[0020] Yet another embodiment relates to a system. The system includes an aftertreatment system coupled to an engine and a controller coupled to the engine, a fuel system, and the aftertreatment system, the controller including one or more processors and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations. The operations include: receiving one or more enable conditions regarding at least one of the engine, the fuel system, or the aftertreatment system; and responsive to receiving the one or more enable conditions: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of a presence of biodiesel in the fuel system.

[0021] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a fueling value regarding a regeneration event; enabling a third flag responsive to determining that the fueling value is at or above a fourth predefined threshold; and enabling a fourth flag responsive to determining that the first temperature is at or below a fifth predefined threshold.

[0022] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a sixth predefined threshold; enabling a fifth flag responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold; receiving a regeneration event stage of a regeneration event; and enabling a sixth flag responsive to the regeneration event stage being during or after a predefined regeneration stage.

[0023] In some embodiments, responsive to receiving the one or more enable conditions, the operations further include enabling the biodiesel detection flag responsive to enabling at least the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag.

[0024] Numerous specific details are provided to impart a thorough understanding of embodiments of the subject matter of the present disclosure. The described features of the subject matter of the present disclosure may be combined in any suitable manner in one or more embodiments and / or implementations. In this regard, one or more features of an aspect of the invention may be combined with one or more features of a different aspect of the invention. Moreover, additional features may be recognized in certain embodiments and / or implementations that may not be present in all embodiments or implementations.BRIEF DESCRIPTION

[0025] FIG. 1 is a block diagram of an engine system, according to an example embodiment. FIG. 2 is a block diagram of a controller of the system of FIG. 1, according to an example embodiment. FIG. 3 is a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4A is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4B is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 5 is an illustration of a graph depicting a temperature deficit over time, according to an example embodiment. DETAILED DESCRIPTION

[0026] Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, computer-readable media, and systems for detecting biodiesel in a fuel system of an internal combustion engine system. A fuel system may facilitate one or more functions in an engine system including, but not limited to, providing fuel to engine components, such as combustion cylinders. Before turning to the Figures, which illustrate certain exemplary embodiments in detail, it should be understood that the present disclosure is not limited to the details or methodology set forth in the description or illustrated in the Figures. It should also be understood that the terminology used herein is for the purpose of description only and should not be regarded as limiting.

[0027] As utilized herein, the term "estimating" and like terms are used to refer to determining a value based on data (e.g., sensor data, historical sensor data, real-time sensor data, etc.), which may be close but not necessarily exactly the actual value. In some embodiments, estimating a current or future value can be performed using one or more models (e.g., statistical models, artificial intelligence models, machine learning models, etc.). For example, estimating a temperature of exhaust gas can include using data, such as sensor data, with a model to determine the temperature value.

[0028] As utilized herein, the term "measuring" and like terms are used to refer to determining an approximate value based on detecting or receiving information regarding the measured value / parameter (e.g., using a sensor). The measured value may be closer to the actual value (e.g., compared to estimating the value) but not necessarily exactly the actual value of the parameter value.

[0029] As used herein, "predicting" and similar terms, in addition to the plain meaning of the words, are used to mean estimating or otherwise determining a future value or characteristic. In some embodiments, predicting the future value can be performed using one or more models (e.g., statistical models, artificial intelligence models, machine learning models, etc.). For example, predicting a temperature of exhaust gas can include using data, such as sensor data, with a model to determine the future temperature value.

[0030] As utilized herein, the term "operational data" and like terms are used to refer to data regarding the operation of a system, such as an engine system. In some embodiments, operational data may include settings, values, or other information regarding the operation of a system. In some embodiments, the operational data may be measured (e.g., by one or more real sensors) and / or estimated or determined (e.g., by one or more virtual sensors or by a computer device or processing circuit).

[0031] As described herein, an engine system may include an engine and an exhaust aftertreatment system in exhaust gas receiving communication with the engine. The engine may be an internal combustion engine (ICE) configured to combust fuel. In some embodiments, the fuel is a petrodiesel fuel. In some embodiments, the fuel is a biodiesel fuel. In some embodiments, the fuel is a blend of biodiesel and petrodiesel. During normal operation of an engine, the ICE may produce various chemicals resulting from combusting the fuel in the presence of air, such as nitrogen oxides (NOx), carbon oxides (CO, CO 2 ), sulfur oxides (SOx), particulate matter, such as ash or soot, and / or other substances resulting from the combustion of the fuel. The products of combustion may be routed out of the engine with exhaust gases and to one or more downstream components, such as an aftertreatment system.

[0032] The exhaust aftertreatment system may include one or more components, such as a particulate filter configured to remove particulate matter, such as soot, from exhaust gas flowing in the exhaust gas conduit system, a dosing module (e.g., a doser) configured to supply a dosing fluid to the exhaust gas flowing in the exhaust gas system, and one or more catalyst devices configured to facilitate conversion of the exhaust gas constituents (e.g., nitrogen oxides, NO x ) to less harmful elements (e.g., water, nitrogen), such as an oxidation catalyst, a selectively catalytic reduction (SCR) system, a three-way catalyst, and so on. A control system or controller may monitor one or more parameters of the components of the engine system using one or more sensors (e.g., actual sensors and / or virtual sensors) to collect and / or determine sensor data. The control system may analyze the sensor data and compare the analyzed sensor data with one or more thresholds.

[0033] Over time, the particulate filter may accumulate particulate matter, reducing the effectiveness of the particulate filter (e.g., reducing the ability of the particulate filter to remove particulate matter from the exhaust gas). The control system may cause a "regeneration event" whereby a temperature of the exhaust gas (e.g., the exhaust gas temperature) increases to at or above a predetermined threshold. When the exhaust gas temperature is at or above the predetermined threshold, at least a portion of the particulate matter accumulated on the particulate filter is burnt off, reducing the amount of particulate matter on the particulate filter.

[0034] In some embodiments, the regeneration event includes causing a predetermined amount of fuel (e.g., biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel) to enter the exhaust aftertreatment system. The oxidation catalyst may facilitate oxidation of the fuel. The oxidation of the fuel is an exothermic reaction that increases the temperature of the exhaust gas. However, when the fuel is or includes biodiesel, the increase in temperature resulting from the oxidation of the fuel may be below the predetermined threshold temperature for the regeneration event. In some embodiments, when the exhaust gas temperature is below the predetermined threshold, the particulate matter accumulated on the particulate filter does not burn off, and the amount of particulate matter accumulated on the particulate filter may increase or remain substantially constant.

[0035] Advantageously and as described herein, the control system or controller may implement one or more controls to detect the presence of biodiesel in the fuel. As described herein, the control system may, responsive to detecting the presence of biodiesel in the fuel, implement one or more controls to adjust the regeneration event to account for the presence of biodiesel in the fuel, such as, for example, increasing the predetermined amount of fuel provided to the aftertreatment system, increasing a frequency of regeneration events (e.g., decreasing the time between regeneration events), providing one or more notifications to a user, such as a mechanic, operator of the engine system, or other suitable user, indicating the presence of biodiesel in the fuel and / or a recommendation to service or replace the particulate filter, and so on.

[0036] Technically and beneficially, the systems, methods, and apparatuses described herein provide an improved control system that enables the control system to determine the presence of biodiesel in the fuel without directly measuring or sensing the chemical composition of the fuel. The control system described herein advantageously utilizes a particular control strategy to identify the presence of biodiesel in the fuel using one or more sensors positioned in the aftertreatment system, such as one or more temperature sensors. That is, the systems and methods described herein provide a technical solution to the technical problem of identifying the presence of biodiesel in fuel, without directly determining the chemical composition of the fuel and / or without the use of specialized sensors configured to sense or detect the chemical composition of the fuel. Advantageously, the presence of biodiesel in fuel is determined using one or more sensors that are typically included in an aftertreatment system, such as, for example, temperature sensors.

[0037] Now referring to FIG. 1, a schematic view of a block diagram of a system 100 (e.g., an engine system) is shown, according to an example embodiment. The system 100 includes an engine 101, an aftertreatment system 120 in exhaust gas receiving communication with the engine 101. The system 100 may also include a controller 140 (as shown in FIG. 2) and an operator input / output (I / O) device 130 (as shown in FIG. 2), where the controller 140 is communicably coupled to each of the aforementioned components. In the configuration of FIG. 1, the system 100 is included in a vehicle. The vehicle may be any type of on-road or off-road vehicle including, but not limited to, wheel-loaders, fork-lift trucks, line-haul trucks, mid-range trucks (e.g., pick-up trucks, etc.), sedans, coupes, tanks, airplanes, boats, and any other type of vehicle. In another embodiment, the system 100 may be embodied in a stationary piece of equipment, such as a power generator or genset. All such variations are intended to fall within the scope of the present disclosure.

[0038] The engine 101 may be any type of internal combustion engine that generates exhaust gas. In the example depicted, the engine 101 is a part of a diesel engine system. The engine 101 is configured to combust a diesel fuel including biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel. In some embodiments, the engine 101 is part of a hybrid engine system having a combination of an internal combustion engine and at least one electric motor coupled to at least one battery. In some embodiments, the hybrid engine system may be configured as a mild-hybrid powertrain, a parallel hybrid powertrain, a series hybrid powertrain, or a series-parallel powertrain.

[0039] As shown in FIG. 1, an intake air throttle (IAT) valve 102, a fuel system 103, and an oil system 104 are coupled to the engine 101. The IAT valve 102 is structured to control an amount of air supplied to the engine 101. The fuel system 103 is structured to provide fuel (e.g., biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel) to the engine 101 (e.g., from a fuel source). The fuel system 103 may control one or more fueling parameters including a fuel amount, a fuel pressure, a fuel injection timing, etc. In some embodiments, the fuel system 103 is or includes a fuel storage device, such as a storage tank. The fuel storage device is configured to store the fuel. In some embodiments, the system 100 may receive the fuel via the fuel system 103 (e.g., at the fuel storage device). The oil system 104 is configured to provide lubricant (e.g., lubricant oil) to the engine 101.

[0040] The IAT valve 102 is a valve positioned at an air inlet of the engine 101. The IAT valve 102 may be actuated (e.g., by an actuator controlled by the controller 140) between an open position and a closed position. In the open position, the IAT valve 102 allows a maximum amount of air to flow from the air intake to the engine 101. In the closed position, the IAT valve 102 allows a minimum amount of air to flow from the air intake to the engine 101. The controller 140 may selectively actuate the IAT valve 102 (e.g., by controlling the actuator) in a plurality of positions between and / or including the open position and the closed position to adjust the amount of air received by the engine 101.

[0041] The aftertreatment system 120 is in exhaust-gas receiving communication with the engine 101. In the example depicted, the aftertreatment system includes a diesel oxidation catalyst (DOC) 121, a diesel particulate filter (DPF) 122, and a selective catalytic reduction (SCR) system 123. In some embodiments, the aftertreatment system 120 includes an ammonia slip catalyst (ASC) 128. The DOC 121, the DPF 122, the SCR 123, and the ASC 128 may be fluidly coupled by an exhaust gas conduit. The DOC 121 is structured to receive the exhaust gas from the engine 101 and to oxidize one or more exhaust gas constituents (e.g., fuel, hydrocarbons, etc.) in the exhaust gas. The DPF 122 is arranged or positioned downstream of the DOC 121 and structured to remove particulates or particulate matter, such as soot, from exhaust gas flowing in the exhaust gas stream. The DPF 122 includes an inlet, where the exhaust gas is received, and an outlet, where the exhaust gas exits after having particulate matter substantially filtered from the exhaust gas. In some implementations, the DPF 122 or other components may be omitted and / or other components added (e.g., a second SCR system having an additional dosing unit or module, multiple DOCs, etc.). Additionally, although a particular arrangement is shown for the aftertreatment system 120 in FIG. 1, the arrangement of components within the aftertreatment system 120 may be different in other embodiments (e.g., the DPF 122 positioned downstream of the SCR 123 and ASC).

[0042] The aftertreatment system 120 may further include a reductant delivery system which may include a decomposition chamber (e.g., decomposition reactor, reactor pipe, decomposition tube, reactor tube, etc.) to convert a reductant into ammonia, shown as a dosing module or unit 124. The reductant may be, for example, urea, diesel exhaust fluid (DEF), Adblue ®< , a urea water solution (UWS), an aqueous urea solution (e.g., AUS32, etc.), and other similar fluids. The dosing module 124 may include a reservoir, a pump, and a nozzle (and potentially other components or devices). The reservoir may be structured to store the reductant. The pump may be fluidly coupled to the reservoir and the nozzle by a dosing conduit and structured to pump the reductant from the reservoir to the nozzle. The nozzle may provide the reductant to the exhaust gas within the exhaust gas conduit. The reductant fluid is added to the exhaust gas stream to aid in the catalytic reduction. As shown in FIG. 1, the reductant may be injected upstream of the SCR 123 generally (or in particular, the SCR catalyst) by the dosing module 124 such that the SCR catalyst receives a mixture of the reductant and exhaust gas. The reductant droplets then undergo the processes of evaporation, thermolysis, and hydrolysis to form gaseous ammonia within the decomposition chamber, the SCR catalyst, and / or the exhaust gas conduit system, which leaves the aftertreatment system 120.

[0043] As indicated above, the aftertreatment system 120 may further include an oxidation catalyst (e.g., the DOC 121) fluidly coupled to the exhaust gas conduit system to oxidize one or more gas constituents (e.g., hydrocarbons, carbon monoxide, etc.) of the exhaust gas. In order to properly assist in this reduction, the DOC 121 may be required to be at a certain operating temperature. In some embodiments, this certain operating temperature is approximately between 200-500 °C. In other embodiments, the certain operating temperature is the temperature at which the conversion efficiency of the DOC 121 exceeds a predefined threshold (e.g., the conversion of HC to less harmful compounds, which is known as the HC conversion efficiency).

[0044] In some embodiments, the DOC 121 is configured to facilitate the oxidation of fuel (e.g., biodiesel, petrodiesel, or a blend of biodiesel and petrodiesel) in the aftertreatment system 120. The oxidation of fuel is an exothermic reaction that increases the temperature of the exhaust gas. Advantageously, when the DOC 121 facilitates the oxidation of the fuel, the temperature of the exhaust gas may increase, thereby increasing the temperature of one or more components of the aftertreatment system 120 downstream of the DOC 121, such as the DPF 122. In various embodiments, the change in temperature of the exhaust gas between an inlet of the DOC 121 and an outlet of the DOC 121 is referred to herein as the "exotherm" of the DOC 121.

[0045] The SCR 123 is configured to assist in the reduction of NO x emissions by accelerating a NOx reduction process between the ammonia and the NO x of the exhaust gas into diatomic nitrogen (N 2 ) and water (H 2 O). If the SCR catalyst is not at or above a certain temperature, the acceleration of the NOx reduction process is limited and the SCR 123 may not be operating at a level of a desired conversion efficiency (i.e., a value indicative of an amount of reduction of NO x emissions, also referred to as "deNO x efficiency"). In some embodiments, this certain temperature is approximately 200-600 °C. The SCR catalyst may be made from a combination of an inactive material and an active catalyst, such that the inactive material (e.g., ceramic substrate) directs the exhaust gas towards the active catalyst, which is any sort of material suitable for catalytic reduction (e.g. metal exchanged zeolite (Fe or Cu / zeolite), base metals oxides like vanadium, molybdenum, tungsten, etc.).

[0046] When ammonia in the exhaust gas does not react with the SCR catalyst (either because the SCR 123 is below operating temperature or because the amount of dosed ammonia greatly exceeds the amount of NO x ), the unreacted ammonia may bind to the SCR catalyst, becoming stored in the SCR 123. This stored ammonia is released from the SCR 123 as the SCR 123 warms, which can cause issues if the amount of ammonia released is greater than the amount of NO x passing through (i.e., more ammonia than needed for the amount of NO x , which can lead to ammonia slip). In some embodiments, the ASC is included and structured to address ammonia slip by removing at least some excess ammonia from the treated exhaust gas before the treated exhaust gas is released into the atmosphere. As exhaust gas passes through the ASC, some of unreacted ammonia (i.e., unreacted with NOx) remaining in the exhaust gas is partially oxidized to NOx, which then consequently reacts with the remaining unreacted ammonia to form N2 gas and water. However, similar to the SCR catalyst, if the ASC is not at or above a certain temperature, the acceleration of the NH3 reduction process is limited and the ASC may not be operating at a level of efficiency to meet regulations or desired parameters. In some embodiments, this certain temperature is approximately 250-300°C.

[0047] As shown, a plurality of sensors 125 are included in the aftertreatment system 120. The number, placement, and type of sensors included in the aftertreatment system 120 are shown for example purposes only. That is, in other configurations, the number, placement, and type of sensors may differ. The sensors 125 may be gas constituent sensors (e.g., NO x sensors, oxygen sensors, etc.), temperature sensors, particulate matter (PM) sensors, flow rate sensors (e.g., mass flow rate sensors, volumetric flow rate sensors, etc.), other exhaust gas emissions constituent sensors, pressure sensors, some combination thereof, and so on. The gas constituent sensors may include an oxygen sensor that is structured to acquire data indicative of the presence of oxygen in the exhaust gas. The data from the oxygen sensor may be used to estimate an air-to-fuel ratio (AFR) value. The flow rate sensors may include a mass air flow (MAF) sensor structured to acquire data indicative of a mass flow rate of the exhaust gas. The temperature sensors are structured to acquire data indicative of a temperature value at each location where the temperature sensor is located.

[0048] The sensors 125 may be located in or proximate the engine 101, after the engine 101 and before the aftertreatment system 120, after the aftertreatment system 120, in the aftertreatment system as shown (e.g., upstream and / or downstream of the DOC 121, the DPF 122, and / or the SCR 123, etc.), upstream of the engine 101, etc. It should be understood that the location of the sensors may vary. In one embodiment, there may be sensors 125 located both before and after the aftertreatment system 120. In one embodiment, at least one of the sensors is structured as exhaust gas constituent sensors (e.g., CO, NOx, PM, SOx, etc. sensors). In another embodiment, at least one of the sensors 125 is structured as non-exhaust gas constituent sensors that are used to estimate exhaust gas emissions (e.g., temperature, flowrate, pressure, etc.). Additional sensors may be also included with the system 100. The sensors may include engine-related sensors (e.g., torque sensors, speed sensors, pressure sensors, flowrate sensors, temperature sensors, etc.). For example, in some embodiments, at least one of the sensors 125 is structured as an oil temperature sensor that is used to detect and / or determine an engine oil temperature. The sensors may further include sensors associated with other components of the vehicle (e.g., speed sensor of a turbo charger, fuel quantity and injection rate sensor, fuel rail pressure sensor, etc.).

[0049] The sensors 125 may be real or virtual (i.e., a non-physical sensor that is structured as program logic in the controller 140 that makes various estimations or determinations). For example, an engine speed sensor may be a real or virtual sensor arranged to measure or otherwise acquire data, values, or information indicative of a speed of the engine 101 (typically expressed in revolutions-per-minute). The sensor is coupled to the engine (when structured as a real sensor) and is structured to send a signal to the controller 140 indicative of the speed of the engine 101. When structured as a virtual sensor, at least one input may be used by the controller 140 in an algorithm, model, lookup table, etc. to determine or estimate a parameter of the engine (e.g., power output, etc.). Any of the sensors 125 described herein may be real or virtual.

[0050] The controller 140 is coupled to and, in particular, communicably coupled, to the sensors 125. Accordingly, the controller 140 is structured to receive data from one or more of the sensors 125 and provide instructions / information to the one or more sensors 125. The received data may be used by the controller 140 to control one or more components in the system 100 and / or for monitoring and thermal management purposes.

[0051] The operator input / output (I / O) device 130 may be coupled to the controller 140, such that information may be exchanged between the controller 140 and the I / O device 130, where the information may relate to one or more components of FIG. 1 or determinations (described below) of the controller 140. The operator I / O device 130 enables an operator of the system 100 to communicate with the controller 140 and one or more components of the system 100 of FIG. 1. For example, the operator input / output device 130 may include, but is not limited to, an interactive display, a touchscreen device, one or more buttons and switches, voice command receivers, etc. In this way, the operator input / output device 130 may provide one or more indications or notifications to an operator, such as a malfunction indicator lamp (MIL), etc. Additionally, the vehicle may include a port that enables the controller 140 to connect or couple to a scan tool so that fault codes and other information regarding the vehicle may be obtained.

[0052] The controller 140 is structured to control, at least partly, the operation of the system 100 and associated sub-systems, such as the engine 101 and the operator I / O device 130. Communication between and among the components may be via any number of wired or wireless connections. For example, a wired connection may include a serial cable, a fiber optic cable, a CAT5 cable, or any other form of wired connection. In comparison, a wireless connection may include the Internet, Wi-Fi, cellular, radio, etc. In one embodiment, a controller area network (CAN) bus provides the exchange of signals, information, and / or data. The CAN bus includes any number of wired and wireless connections. Because the controller 140 is communicably coupled to the systems and components of FIG. 1, the controller 140 is structured to receive data from one or more of the components shown in FIG. 1. The structure and function of the controller 140 is further described in regard to FIG. 2.

[0053] As the components of FIG. 1 are shown to be embodied in the system 100, the controller 140 may be structured as one or more electronic control units (ECUs), such as one or more microcontrollers. The controller 140 may be separate from or included with at least one of a transmission control unit, an exhaust aftertreatment control unit, a powertrain control module, an engine control module, etc.

[0054] Now referring to FIG. 2, a schematic diagram of the controller 140 of the system 100 of FIG. 1 is shown, according to an example embodiment. As shown, the controller 140 includes at least one processing circuit 202 having at least one processor 204 and at least one memory device 206, a biodiesel detection circuit 212, and a communications interface 216. The controller 140 is structured to monitor the engine 101 and the aftertreatment system 120 to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103) based on, for example, monitoring the engine and / or the aftertreatment system 120.

[0055] In one configuration, the biodiesel detection circuit 212 is embodied as machine or computer-readable media storing instructions that are executable by a processor, such as processor 204. As described herein and amongst other uses, the machine-readable media facilitates performance of certain operations to enable reception and transmission of data. For example, the machine-readable media may provide an instruction (e.g., command, etc.) to, e.g., acquire data. In this regard, the machine-readable media may include programmable logic that defines the frequency of acquisition of the data (or, transmission of the data). The computer readable media instructions may include code, which may be written in any programming language including, but not limited to, Java or the like and any conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may be executed on one processor or multiple remote processors. In the latter scenario, the remote processors may be connected to each other through any type of network (e.g., CAN bus, etc.).

[0056] In another configuration, biodiesel detection circuit 212 is embodied as one or more hardware units, such as one or more electronic control units. As such, biodiesel detection circuit 212 may be embodied as one or more circuitry components including, but not limited to, processing circuitry, network interfaces, peripheral devices, input devices, output devices, sensors, etc. In some embodiments, the biodiesel detection circuit 212 may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (IC), discrete circuits, system on a chip (SOCs) circuits, microcontrollers, etc.), telecommunication circuits, hybrid circuits, and any other type of "circuit." In this regard, biodiesel detection circuit 212 may include any type of component for accomplishing or facilitating the achievement of the operations described herein. For example, a circuit as described herein may include one or more transistors, logic gates (e.g., NAND, AND, NOR, OR, XOR, NOT, XNOR, etc.), resistors, multiplexers, registers, capacitors, inductors, diodes, wiring, and so on. The biodiesel detection circuit 212 may also include or be programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like. The biodiesel detection circuit 212 may include one or more memory devices for storing instructions that are executable by the processor(s) of the biodiesel detection circuit 212. The one or more memory devices and processor(s) may have the same definition as provided below with respect to the memory device 206 and processor 204. In some hardware unit configurations, the biodiesel detection circuit 212 may be geographically dispersed throughout separate locations in the vehicle. Alternatively and as shown, the biodiesel detection circuit 212 may be embodied in or within a single unit / housing, which is shown as the controller 140.

[0057] In the example shown, the controller 140 includes the processing circuit 202 having the processor 204 and the memory device 206. The processing circuit 202 may be structured or configured to execute or implement the instructions, commands, and / or control processes described herein with respect to the biodiesel detection circuit 212. The depicted configuration represents the biodiesel detection circuit 212 being embodied as machine or computer-readable media storing instructions. However, as mentioned above, this illustration is not meant to be limiting as the present disclosure contemplates other embodiments where the biodiesel detection circuit 212 is configured as a hardware unit. All such combinations and variations are intended to fall within the scope of the present disclosure.

[0058] The processor 204 may be implemented as one or more single- or multi-chip processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), and / or suitable processors (e.g., other programmable logic devices, discrete hardware components, etc. to perform the functions described herein). A processor may be a microprocessor, a group of processors, etc. A processor also may be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some embodiments, the one or more processors may be shared by multiple circuits (e.g., the biodiesel detection circuit 212 may comprise or otherwise share the same processor which, in some example embodiments, may execute instructions stored, or otherwise accessed, via different areas of memory). Alternatively or additionally, the one or more processors may be structured to perform or otherwise execute certain operations independent of one or more co-processors. In other example embodiments, two or more processors may be coupled via a bus to enable independent, parallel, pipelined, or multi-threaded instruction execution. All such variations are intended to fall within the scope of the present disclosure.

[0059] The memory device 206 (e.g., memory, memory unit, storage device) may include one or more devices (e.g., RAM, ROM, Flash memory, hard disk storage) for storing data and / or computer code for completing or facilitating the various processes, layers and modules described in the present disclosure. For example, the memory device 206 may include dynamic random-access memory (DRAM). The memory device 206 may be communicably connected to the processor 204 to provide computer code or instructions to the processor 204 for executing at least some of the processes described herein. Moreover, the memory device 206 may be or include tangible, non-transient volatile memory or non-volatile memory. Accordingly, the memory device 206 may include database components, object code components, script components, or any other type of information structure for supporting the various activities and information structures described herein.

[0060] The communications interface 216 may include any combination of wired and / or wireless interfaces (e.g., jacks, antennas, transmitters, receivers, transceivers, wire terminals) for conducting data communications with various systems, devices, or networks structured to enable in-vehicle communications (e.g., between and among the components of the vehicle) and out-of-vehicle communications (e.g., with a remote server). For example and regarding out-of-vehicle / system communications, the communications interface 216 may include an Ethernet card and port for sending and receiving data via an Ethernet-based communications network and / or a Wi-Fi transceiver for communicating via a wireless communications network. The communications interface 216 may be structured to communicate via local area networks or wide area networks (e.g., the Internet) and may use a variety of communications protocols (e.g., IP, LON, Bluetooth, ZigBee, radio, cellular, near field communication).

[0061] In various embodiments, the controller 140 and / or one or more components thereof, such as the biodiesel detection circuit 212, is configured to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103). Advantageously, the controller 140 is configured to determine the presence of biodiesel in the system 100 without directly measuring or sensing the chemical composition of fuel stored in the system 100.

[0062] In some embodiments, the controller 140 is configured to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103) responsive to receiving one or more enable conditions. As described herein, an "enable condition" refers to a predefined operating condition of the system 100. The enable condition may be received or determined by the controller 140 based on a control signal or other information received by the controller 140, such as a predefined condition detected by one or more sensors 125.

[0063] In some embodiments, the enable condition includes receiving a regeneration event trigger. The regeneration event trigger is or is indicative of a condition or plurality of conditions that triggers a regeneration event. The regeneration event trigger may be a predefined duration (e.g., an amount of time or a distance traveled by the system 100) since a most recent regeneration event elapsing (e.g., based on the controller 140 initiating a timer to track the time since a last regeneration event or a location of the system 100), a detected or determined pressure value (e.g., a pressure change) being at or above a predefined threshold across one or more components of the aftertreatment system 120 (e.g., the DOC 121, the DPF 122, etc.), and / or a user input received via an input / output device of the system.

[0064] In some embodiments, the enable condition includes an engine fault value. In one embodiment, the enable condition is based on the engine fault value indicating that a number of engine faults that are active is at or below a predefined threshold. In another embodiment, the engine fault value is based on the content associated with the active, if any, faults or fault codes. In yet another embodiment, the enable condition comprising the engine fault value is based on a combination of the number of faults and the content of the faults. As described herein, a "fault code" refers to an onboard diagnostic code (e.g., an OBD-II code, etc.) indicative of a status or characteristic of one or more components of the system 100. In some embodiments, the engine fault codes may be indicative of an issue with the operation of the engine 101, such as an issue with the coolant or oil system 104 (e.g., a coolant temperature at or below a predefined threshold, a coolant amount at or below a predefined threshold), an issue with the fuel system 103 (e.g., an AFR above a predefined threshold, an AFR below a predefined threshold, etc.), an issue with one or more cylinders of the engine 101 (e.g., one or more cylinders misfiring), and so on. In situations where no fault codes corresponding to the engine 101 are active, the engine fault may include an indication that no fault codes corresponding to the engine 101 are active.

[0065] In some embodiments, the enable condition includes an aftertreatment system sensor fault value. In one embodiment, the enable condition is based on the aftertreatment system sensor fault value indicating that a number of aftertreatment system sensor faults that are active is at or below a predefined threshold. In another embodiment, the aftertreatment system sensor fault value is based on the content associated with the active, if any, faults or fault codes. In yet another embodiment, the enable condition comprising the aftertreatment system sensor fault value is based on a combination of the number of faults and the content of the faults. In some embodiments, the fault codes corresponding to one or more sensors 125 associated with the aftertreatment system 120 may indicate, for example, an issue with a sensor, such as a sensor not reporting data, a sensor reporting data outside a predefined range or outside a predefined set of values (e.g., temperatures lower than ambient, temperatures higher than engine combustion temperatures, pressures lower than a predefined value, pressure higher than a predefined value, etc.), and / or other issues related to the one or more sensors 125 associated with the aftertreatment system 120. In situations where no fault codes corresponding to the one or more sensors 125 associated with the aftertreatment system 120 are active, the aftertreatment system sensor fault may include an indication that no fault codes corresponding to the one or more sensors 125 associated with the aftertreatment system 120 are active.

[0066] In some embodiments, the enable condition includes a system fault value. In one embodiment, the enable condition is based on the system fault value indicating that a number of system faults that are active is at or below a predefined threshold. In another embodiment, the system fault value is based on the content associated with the active, if any, faults or fault codes. In yet another embodiment, the enable condition comprising the system fault value is based on a combination of the number of faults and the content of the faults. In some embodiments, the system fault codes may be indicative of an issue with the operation of the system 100, such as an issue with the engine 101, the aftertreatment system 120 (e.g., a conversion rate of NOx at or below a predefined value, etc.), and so on. In situations where no fault codes corresponding to the system 100 are active, the engine fault may include an indication that no fault codes corresponding to the system 100 are active.

[0067] In some embodiments, the enable condition includes an indication regarding an amount of time a component(s) or system of the aftertreatment system, such as the DOC 121, has been operating at or below a predefined time threshold. The amount of time the component (e.g., DOC 121) has been operating may be measured from a time when the component (e.g., DOC 121) was first installed in the aftertreatment system 120. In another embodiment, the time may only correspond to when the engine 101 is operating (e.g., combusting fuel) and not from an installation date as that installation date may include large periods of inactivity. The amount of time the component (e.g., DOC 121) has been operating may be tracked in a variety of units (e.g., hours, days, etc.). The controller 140 may receive or determine the enable condition responsive to the amount of time the component (e.g., DOC 121) has been operating being at or below a predefined threshold.

[0068] In some embodiments, the enable condition is based on an efficiency of one or more components or systems. For example, the controller 140 may track, receive, and / or determine an efficiency value of the DOC 121. When the efficiency of the DOC 121 is at or above a predefined threshold, the controller 140 determines the enable condition is present. The efficiency value of the DOC 121 is based on an amount of fuel oxidized by the DOC 121 relative to an amount of fuel provided to the aftertreatment system 120. For example, the efficiency value of the DOC 121 may be a ratio of the amount of fuel oxidized by the DOC 121 to the amount of fuel provided to the aftertreatment system 120, expressed as a percentage. The amount of fuel provided to the aftertreatment system 120 is a predefined value. For example, the amount of fuel provided to the aftertreatment system 120 can be based on a control signal request the amount of fuel be provided to the aftertreatment system 120 or another predetermined value. The amount of fuel oxidized by the DOC 121 is based on a measured value. In one embodiment, the measured value is an amount of fuel detected downstream of the DOC 121, and the amount of fuel oxidized by the DOC 121 is the amount of fuel be provided to the aftertreatment system 120 minus the amount of fuel detected downstream of the DOC 121. In another embodiment, the measured value is a temperature value regarding the DOC 121, and the amount of fuel oxidized by the DOC 121 is determined based on, e.g., a lookup table that correlates the temperature value regarding the DOC 121 with the amount of fuel oxidized by the DOC 121. Thus, when all of the fuel provided to the aftertreatment system 120 is oxidized by the DOC 121, the efficiency value of the DOC 121 is 100%, and when half of the fuel provided to the aftertreatment system 120 is oxidized by the DOC 121, the efficiency value of the DOC 121 is 50%. In some embodiments, when the DOC 121 oxidizes less than 100% of the fuel provided to the aftertreatment system 120 at least a portion of the unoxidized fuel is provided to the DPF 122, and the DPF 122 facilitates oxidation of the fuel. In some embodiments, the predefined threshold is 80%.

[0069] In some embodiments, the enable condition includes one or more of the conditions described above and herein. For example, the enable condition may include each of the aforementioned conditions. In another example, the enable condition may include only one or a subset of the aforementioned conditions.

[0070] In some embodiments, responsive to receiving the enable condition, the controller 140 is configured to selectively determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103).

[0071] In one embodiment, the presence of biodiesel in the system 100 (e.g., in the fuel system 103) may be determined based on receiving information regarding the operation of the aftertreatment system 120. The controller 140 may receive one or more "flags" indicative of the operation of the aftertreatment system 120. As described herein, a "flag" refers to a computer-based indication of an operating characteristic of the system 100. In some embodiments a flag may be a binary indication (e.g., indicating true or false), a numeric value, such as a string value or a float value, or other indication. The flag may be stored in the memory of the controller 140. For example, a flag may indicate whether a particular operational data value regarding the operation of the system 100 does not satisfy a corresponding threshold (e.g., at or above a maximum threshold, at or below a minimum threshold, etc.). In some embodiments, the controller 140 is configured to count a number of times a particular flag (e.g., a first flag) has occurred within a predetermined time period. In these embodiments, another flag (e.g., a second flag) may be used to indicate whether a number of times that the first flag occurred is at or above a predefined threshold. A flag may be enabled or activated responsive to one or more predetermined conditions. A flag may be disabled or deactivated responsive to one or more different predetermined conditions, or a flag may be disabled or deactivated by default. In any of the above-described embodiments, the controller 140 may use multiple flags (e.g., more than one) to determine the presence of biodiesel in the system 100 (e.g., in the fuel system 103). Advantageously, the use of more than one flag may mitigate the risk of errant results, such as false positives (e.g., determining that biodiesel is present in the fuel system 103 when biodiesel is not present) and / or false negatives (e.g., determining that biodiesel is not present in the fuel system 103 when biodiesel is present).

[0072] In some embodiments, a first flag is activated based on a rate of change of a duration of a regeneration event. The "duration" of the regeneration event may be determined and / or measured by a counter that increments or counts during a "healthy" regeneration event. A regeneration event is "healthy" when one or more operating conditions of the aftertreatment system 120 are satisfied, such as one or more temperatures of the aftertreatment system 120, a component thereof, or a gas flowing therethrough, being at or above a predetermined temperature threshold. For example, the controller 140 may receive a first temperature regarding a first component of the aftertreatment system 120, such as the DOC 121. The first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may compare the first temperature regarding the DOC 121 to a predefined threshold. In some embodiments, the predefined threshold is between 200 °C and 500 °C (e.g., 300 °C). Responsive to determining that the first temperature regarding the DOC 121 is at or above the predefined threshold, the controller 140 may determine that the regeneration event is healthy. In another example, the controller 140 may determine that the regeneration event is "healthy" based on another operational characteristic of the aftertreatment system, such as a pressure value regarding the DOC 121 or the DPF 122. Accordingly, the "duration of a regeneration event" is based on a period of time during which, the temperature value of the exhaust gas and / or a component / system within in the aftertreatment system 120 is at or above the predefined threshold and a pressure value regarding one or more components of the aftertreatment system 120 (e.g., the DOC 121, the DPF 122, etc.) is at or above a predefined threshold. When these conditions are met, the controller 140 may track and / or determine the duration of the regeneration event (e.g., by incrementing the counter or counter parameter). The counter parameter is held constant (e.g., is not incremented) when the regeneration is not healthy (e.g., when one or temperature values regarding the aftertreatment system 120 is below a corresponding threshold, when one or more pressure values regarding the aftertreatment system 120 is below a corresponding threshold, etc.). The rate of change of the regeneration event duration is then based on a change in the regeneration event duration (e.g., the counter parameter value) over a predefined time period, such as one day, one week, one month, etc., for a single regeneration event. The controller 140 may receive or determine the rate of change of the regeneration event duration. The controller 140 may compare the rate of change of the regeneration event duration to a predefined threshold (e.g., a value between 0 and 1, inclusive, such as 0). Responsive to the rate of change of the regeneration event duration being above the predefined threshold (e.g., when the rate of change of the duration of a regeneration is greater than zero), the controller 140 may enable the first flag. Responsive to the rate of change of the regeneration event duration being at or below the predefined threshold (e.g., when the rate of change of the duration of a regeneration is at or below zero), controller 140 does not enable the first flag.

[0073] In some embodiments, a second flag is activated based on an inlet temperature of an aftertreatment system and, namely, the DOC 121. The controller 140 may receive the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may compare the first temperature regarding the DOC 121 to a predefined threshold. In some embodiments, the predefined threshold is between 300 °C and 700 °C (e.g., 500 °C). Responsive to the DOC inlet temperature being at or below the predefined threshold, the controller 140 may enable the second flag.

[0074] In some embodiments, a third flag is activated based on an a fueling value (e.g., fueling rate, a fueling amount, etc.) during a regeneration event, referred to herein as a regeneration fueling value. More specifically, the regeneration fueling value is an amount of fuel provided to the aftertreatment system 120 during a regeneration. The fuel provided to the aftertreatment system 120 is oxidized (e.g., at the DOC 121) in an exothermic reaction, thereby increasing the temperature of the exhaust in the aftertreatment system 120. The controller 140 may receive a fueling value associated with a regeneration event. The fueling value may be a flow rate (e.g., a mass flow rate, a volumetric flow rate, etc.) of fuel provided to the aftertreatment system 120 during a regeneration event. For example, the fueling value may be measured in grams of fuel per second (g / s). The controller 140 may compare the fueling value to a predefined threshold. In some embodiments, the predefined threshold is between 0.25 g / s and 1 g / s (e.g., 0 / 5 g / s). Responsive to the fueling value being at or above the predefined threshold, the controller 140 may enable the third flag.

[0075] In some embodiments, a fourth flag is activated based on a regeneration stage. In various embodiments, the regeneration event may include one or more stages, such as a first stage, a second stage, a third stage, and so on. In an example embodiment, the regeneration event includes five stages. Each stage corresponds to one of a target temperature value or a target temperature ramp rate (e.g., a change in temperature per unit time. The first stage corresponds to a first target temperature value, such as approximately 350 °C. The regeneration event is in the first stage when at least one temperature value regarding the aftertreatment system 120, a component thereof, or a gas flowing therethrough, is at or above the first target temperature value. The second stage corresponds to a first target temperature ramp rate. The regeneration event is in the second stage when the controller 140 sends a command to one or more components of the system 100, such as the engine 101, to increase the at least one temperature value regarding the aftertreatment system 120 at or above the first target temperature ramp rate. The third stage corresponds to a second target temperature value, such as approximately 500 °C. The regeneration event is in the third stage when the at least one temperature value regarding the aftertreatment system 120 is at or above the second target temperature value. The fourth stage corresponds to a second target temperature ramp rate. The regeneration event is in the fourth stage when the controller 140 sends a command to one or more components of the system 100, such as the engine 101, to increase the at least one temperature value regarding the aftertreatment system 120 at or above the second target temperature ramp rate. The fifth stage corresponds to a third target temperature value, such as approximately 600 °C. The regeneration event is in the fifth stage when the at least one temperature value regarding the aftertreatment system 120 is at or above the third target temperature value.

[0076] The controller 140 may receive information regarding the regeneration event stage, such as a current regeneration event stage. The controller 140 may compare the current regeneration event stage to a predefined threshold. In some embodiments, the predefined threshold is one of the stages of the regeneration event, such as a fifth stage. Responsive to the current stage of the regeneration event being during or after the predefined threshold stage (e.g., during or after the fifth stage), the controller 140 may enable the fourth flag.

[0077] In some embodiments, a fifth flag is activated based on a number of occurrences that an exotherm value (e.g., a DOC exotherm value) is at or below a predefined threshold for a predefined duration. The controller 140 may receive the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may receive a second temperature regarding a first component of the aftertreatment system 120, such as the DOC 121. The second temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an outlet of the DOC 121 (e.g., a DOC outlet temperature). In some embodiments, the controller 140 may receive the second temperature from one or more sensors 125 positioned downstream of the DOC 121. The controller 140 may determine the exotherm of the DOC 121 based on the first temperature and the second temperature. As described above the exotherm of the DOC 121 is the change in temperature of the exhaust gas between the inlet of the DOC 121 and the outlet of the DOC 121. The controller 140 may compare the exotherm of the DOC 121 to a predefined threshold. The controller 140 may iteratively determine the exotherm of the DOC 121 and compare the exotherm of the DOC 121 to the predefined threshold for a predefined duration. Responsive to determining that the exotherm of the DOC 121 is at or below the predefined threshold during the predefined duration, the controller 140 may increment a counter (e.g., by increasing a counter value by one). The controller 140 may compare the counter value to a predefined counter threshold. Responsive to the counter value being at or above the predefined counter threshold, the controller 140 may enable the fifth flag.

[0078] In some embodiments, a sixth flag is activated based on a comparison between an expected exotherm of the DOC 121 and the determined exotherm of the DOC 121. The controller 140 may receive the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121. The controller 140 may receive an expected temperature regarding the outlet of the DOC 121 (e.g., an expected DOC outlet temperature). The expected DOC outlet temperature occurs at a future time and / or future operation of the system 100 and is based on the operation of the system 100. In some embodiments, the expected DOC outlet temperature is determined using one or more of a lookup table and / or a model (e.g., a statical model, a physics model, a machine learning model, etc.) that correlates one or more operating conditions of the engine 101, such as an air-to-fuel ratio, a combustion temperature, an engine speed, an engine load, and so on, with the expected DOC outlet temperature. The controller 140 may determine the expected exotherm of the DOC 121 based on a difference between the DOC inlet temperature and the expected DOC outlet temperature. The controller 140 may determine an actual exotherm of the DOC 121. As described above, the DOC 121 may determine the exotherm of the DOC 121 based on, for example, the DOC inlet temperature and the DOC outlet temperature. The controller 140 may determine a difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121. The controller 140 may compare the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 with a predetermined threshold. Responsive to the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 being at or below the predetermined threshold, the controller 140 may enable the sixth flag. In other embodiments, the controller 140 may receive a target DOC outlet temperature (e.g., a desired DOC outlet temperature) that is used instead of the expected DOC outlet temperature.

[0079] In some embodiments, a biodiesel detection flag (e.g., a seventh flag) may be enabled by the controller 140 based on one or more of the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and / or the sixth flag being enabled. For example, the controller 140 may enable the seventh flag responsive to enabling the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag. Advantageously, waiting for each of the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag to be enabled before enabling the seventh flag may mitigate the risk of errant results, such as false positives (e.g., determining that biodiesel is present in the fuel system 103 when biodiesel is not present) and / or false negatives (e.g., determining that biodiesel is not present in the fuel system 103 when biodiesel is present).

[0080] In some embodiments, the controller 140 may determine a number of times the seventh flag (e.g., the biodiesel detection flag) has been enabled during a predetermined period of time and / or operation of the system. For example, the controller 140 may increment (e.g., increase by one) a counter each time the seventh flag is enabled during a predetermined period of time. In some embodiments, the controller 140 may compare a counter value (e.g., the number of times the seventh flag was enabled during the predetermined period of time) to a predetermined threshold. Responsive to determining that the counter value is at or above the predetermined threshold, the controller 140 may determine that biodiesel fuel is present in the system 100 (e.g., in the fuel system 103).

[0081] In some embodiments, responsive to determining that biodiesel fuel is present in the system 100 (e.g., in the fuel system 103), the controller 140 may generate and provide a notification indicating the presence of biodiesel in the fuel system 103. For example, the controller 140 may cause the operator I / O device to display an indication of the presence of biodiesel in the fuel system 103, such as illuminating a lamp, displaying the notification on a display, and so on. In another example, the controller 140 may provide the notification to a user device (e.g., a cellphone, a laptop, a computer, etc.) via one or more of an email message, a text message, a pop-up notification, and so on. In yet another example, the controller 140 may enable one or more fault codes indicative of biodiesel being present in the fuel system 103.

[0082] FIG. 3 is a flow diagram of a method 300 of determining the presence of biodiesel in the fuel system 103, according to an example embodiment. In particular, the controller 140 (and / or one or more components thereof) is structured to perform the method 300. In some embodiments, some of the processes of method 300 may be combined, performed in a different order, and / or omitted. In still other embodiments, additional processes may be added to the method 300 without departing from the scope of the disclosure.

[0083] At process 302, the controller 140 receives or determines a regeneration event trigger. The controller 140 may receive a first enable condition responsive to receiving the regeneration event trigger.

[0084] At process 304, the controller 140 receives an engine fault value indicating a number of engine faults that are active, the content associated with the active fault codes, or both. The controller 140 may receive a second enable condition responsive to the engine fault value being at or below the predefined threshold.

[0085] At process 306, the controller 140 receives an aftertreatment system sensor fault value indicating a number of aftertreatment system sensor faults that are active, the content associated with the active fault codes, or both. The controller 140 may receive a third enable condition responsive to the aftertreatment system sensor fault value being at or below the predefined threshold.

[0086] At process 308, the controller 140 receives a system fault value indicating that a number of system faults that are active, the content associated with the active fault codes, or both. The controller 140 may receive a fourth enable condition responsive to the system fault value being at or below the predefined threshold.

[0087] At process 310, the controller 140 receives an indication that an amount of time the DOC 121 has been operating at or below a predefined threshold. The controller 140 may receive a fifth enable condition responsive to the amount of time the DOC 121 has been operating at or below a predefined threshold.

[0088] At process 312, the controller 140 receives an indication that an efficiency value of the DOC 121 is at or above a predefined threshold. The controller 140 may receive a sixth enable condition responsive to the efficiency value of the DOC 121 being at or above the predefined threshold.

[0089] At process 314, the controller 140 executes an "exotherm logic" or exotherm process. The exotherm logic may be or include one or more processes for determining the presence of biodiesel in the fuel system 103. An example exotherm logic is shown and described herein, with respect to FIGS. 4A and 4B. In some embodiments, the controller 140 executes the exotherm logic responsive to receiving one or more enable conditions. The exotherm logic may be stored as instructions within the memory of the controller that is selectively executed by one or more processors of the controller 140. In an example embodiment, the controller 140 executes the exotherm logic responsive to receiving the first enable condition, the second enable condition, the third enable condition, the fourth enable condition, the fifth enable condition, and the sixth enable condition. In some embodiments, the controller 140 is configured to prevent execution of the exotherm logic when the controller 140 does not receive at least one of the first enable condition, the second enable condition, the third enable condition, the fourth enable condition, the fifth enable condition, or the sixth enable condition. Advantageously, by preventing execution of the exotherm logic when one or more of the enable conditions are not received, the controller 140 may mitigate errant results from the exotherm logic (e.g., false positive and / or false negative results).

[0090] At process 316, the controller 140 may provide an indication of biodiesel in the system 100 (e.g., in the fuel system 103). The controller 140 may generate and provide a notification indicating the presence of biodiesel in the system 100 (e.g., in the fuel system 103). For example, the controller 140 may cause the operator I / O device to display an indication of the presence of biodiesel in the fuel system 103, such as illuminating a lamp, displaying the notification on a display, and so on. In another example, the controller 140 may provide the notification to a user device (e.g., a cellphone, a laptop, a computer, etc.) via an email message, a text message, a pop-up notification, or other suitable notification. In yet another example, the controller 140 may enable one or more fault codes indicative of biodiesel being present in the fuel system 103.

[0091] FIGS. 4A and 4B depict a flow diagram of a method 400 of determining the presence of biodiesel in the fuel system 103, according to an example embodiment. In particular, the controller 140 is structured to perform the method 400. In some embodiments, some of the processes of method 400 may be combined, performed in a different order, and / or omitted. In still other embodiments, additional processes may be added to the method 400 without departing from the scope of the disclosure.

[0092] At process 402, The controller 140 receives or determines a first temperature regarding a first component and / or system of the aftertreatment system 120, such as the DOC 121. The first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121.

[0093] At process 404, the controller 140 compares the first temperature regarding the DOC 121 to a predefined threshold. Responsive to determining that the first temperature regarding the DOC 121 is at or above the predefined threshold, the controller 140 proceeds to process 406.

[0094] At process 406, the controller 140 receives or determines a rate of change of a regeneration event duration. At process 408, the controller 140 may compare the rate of change of the regeneration event duration to a predefined threshold. Responsive to the rate of change of the regeneration event duration being at or below the predefined threshold, the controller 140 may enable a first flag. Responsive to enabling the first flag, the controller 140 may proceed to process 450.

[0095] At process 410, the controller 140 receives or determines the first temperature regarding the DOC 121. As described above, the first temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an inlet of the DOC 121 (e.g., a DOC inlet temperature). In some embodiments, the controller 140 may receive the first temperature from one or more sensors 125 positioned upstream of the DOC 121.

[0096] At process 412, the controller 140 compares the first temperature regarding the DOC 121 to a predefined threshold. Responsive to the DOC inlet temperature being at or below the predefined threshold, the controller 140 may enable a second flag. Responsive to enabling the second flag, the controller 140 may proceed to process 450. In some embodiments, processes 410-412 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408.

[0097] At process 414, the controller 140 receives or determines a fueling rate associated with a regeneration event (e.g., the regeneration fueling value). At process 416, the controller 140 compares the fueling rate to a predefined threshold. Responsive to the fueling rate being at or above the predefined threshold, the controller 140 may enable a third flag. Responsive to enabling the third flag, the controller 140 may proceed to process 450. In some embodiments, processes 414-416 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408 and / or process 410-412.

[0098] At process 418, the controller 140 receives or determines information regarding the regeneration event stage, such as a current regeneration event stage. At process 420, the controller 140 compares the current regeneration event stage to a predefined threshold. Responsive to the current stage of the regeneration event being during or after the predefined threshold stage, the controller 140 may enable a fourth flag. Responsive to enabling the fourth flag, the controller 140 may proceed to process 450. In some embodiments, processes 418-420 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408, process 410-412, and / or processes 414-416.

[0099] At process 422, the controller receives or determines the first temperature regarding the DOC 121 (e.g., similar to process 402 and / or process 410). At process 424, the controller 140 receives a second temperature regarding a first component of the aftertreatment system 120, such as the DOC 121. The second temperature regarding the DOC 121 may be a temperature of the exhaust gas at or proximate an outlet of the DOC 121 (e.g., a DOC outlet temperature). In some embodiments, the controller 140 may receive the second temperature from one or more sensors 125 positioned downstream of the DOC 121.

[0100] At process 426, the controller 140 receives or determines an exotherm of the DOC 121 (e.g., an exotherm value or a DOC exotherm value) based on the first temperature and the second temperature. At process 428, the controller 140 compares the exotherm value to a predefined threshold. At process 430, the controller 140 may iteratively determine the exotherm value and compare the exotherm value to the predefined threshold during a predefined duration. Responsive to determining that the exotherm of the DOC 121 was at or below the predefined threshold during the predefined duration, the controller 140 may increment a counter (e.g., by increasing a counter value by one).

[0101] At process 432, the controller 140 compares the number of occurrences of the exotherm value being at or below the predefined threshold for the predefined duration (e.g., the counter value) to a predefined occurrences threshold. Responsive to the counter value is at or above the predefined occurrences threshold, the controller 140 may enable a fifth flag. Responsive to enabling the fifth flag, the controller 140 may proceed to process 450. In some embodiments, processes 422-432 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408, process 410-412, processes 414-416, and / or process 418-420.

[0102] At process 434, the controller 140 receives or determines the first temperature regarding the DOC 121. At process 436, the controller 140 receives an expected DOC outlet temperature. At process 438, the controller 140 determines the expected exotherm of the DOC 121 (e.g., an expected exotherm value or an expected DOC exotherm value) based on a difference between the DOC inlet temperature and the expected DOC outlet temperature.

[0103] At process 440, the controller 140 receives or determines an actual exotherm value (e.g., an actual DOC exotherm value). For example, the controller 140 may receive information regarding the first temperature and / or the second temperature. In another example, the controller 140 may determine the actual exotherm value (e.g., at process 428).

[0104] At process 442, the controller 140 may receive or determine a difference between the expected exotherm value and the actual exotherm value. At process 444, the controller 140 compares the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 with a predetermined threshold. Responsive to the difference between the expected exotherm of the DOC 121 and the actual exotherm of the DOC 121 being at or below the predetermined threshold, the controller 140 may enable a sixth flag. Responsive to enabling the sixth flag, the controller 140 may proceed to process 450. In some embodiments, processes 434-444 may be performed concurrently, partially concurrently or sequentially (e.g., before or after) processes 402-408, process 410-412, processes 414-416, process 418-420, and / or process 422-432.

[0105] At process 450, the controller 140 may enable a biodiesel detection flag (e.g., a seventh flag), responsive to receiving and / or enabling one or more of the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and / or the sixth flag being enabled. In an example embodiment, the controller 140 may enable the seventh flag responsive to enabling the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag.

[0106] At process 452, the controller 140 may receive or determine a number of times the seventh flag has been enabled during a predetermined period of time. At process 454, the controller 140 may determine the presence of biodiesel in the fuel system 103, responsive to determining that the number of times the seventh flag has been enabled during a predetermined period of time is at or above a predetermined threshold. In some embodiments, after performing the method 400, the controller may proceed to process 316 of the method 300.

[0107] FIG. 5 is an illustration of a graph 500. The graph 500 depicts a temperature deficit over time. The temperature deficit is a difference between a target temperature value and an actual temperature value. More specifically, the temperature deficit depicted in the graph 500 is a temperature deficit of a component of the aftertreatment system 120, such as the DOC 121. A first curve 502 represents the temperature deficit when the fuel in the fuel system 103 includes biodiesel. A second curve 504 represents the temperature deficit when the fuel in the fuel system 103 does not include biodiesel.

[0108] During a first period of time 510, the controller 140 may receive each of the enable conditions and execute the exotherm logic. Responsive to executing the exotherm logic during the first period of time 510, the controller 140 may determine the presence of biodiesel in the fuel system 103. During a second period of time 512, the controller 140 may receive each of the enable conditions and execute the exotherm logic. Responsive to executing the exotherm logic during the second period of time 512, the controller 140 may determine the presence of biodiesel in the fuel system 103.

[0109] As utilized herein, the terms "approximately," "about," "substantially", and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the disclosure as recited in the appended claims.

[0110] It should be noted that the term "exemplary" and variations thereof, as used herein to describe various embodiments, are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (and such terms are not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0111] The term "coupled" and variations thereof, as used herein, means the joining of two members directly or indirectly to one another. Such joining may be stationary (e.g., permanent or fixed) or moveable (e.g., removable or releasable). Such joining may be achieved with the two members coupled directly to each other, with the two members coupled to each other using one or more separate intervening members, or with the two members coupled to each other using an intervening member that is integrally formed as a single unitary body with one of the two members. If "coupled" or variations thereof are modified by an additional term (e.g., directly coupled), the generic definition of "coupled" provided above is modified by the plain language meaning of the additional term (e.g., "directly coupled" means the joining of two members without any separate intervening member), resulting in a narrower definition than the generic definition of "coupled" provided above. Such coupling may be mechanical, electrical, or fluidic. For example, circuit A communicably "coupled" to circuit B may signify that the circuit A communicates directly with circuit B (i.e., no intermediary) or communicates indirectly with circuit B (e.g., through one or more intermediaries).

[0112] References herein to the positions of elements (e.g., "top," "bottom," "above," "below") are merely used to describe the orientation of various elements in the FIGURES. It should be noted that the orientation of various elements may differ according to other exemplary embodiments, and that such variations are intended to be encompassed by the present disclosure.

[0113] While various circuits with particular functionality are shown in FIG. 2, it should be understood that the controller 140 may include any number of circuits for completing the functions described herein. For example, the activities and functionalities of the biodiesel detection circuit 212 may be combined in multiple circuits or as a single circuit. Additional circuits with additional functionality may also be included. Further, the controller 140 may further control other activity beyond the scope of the present disclosure.

[0114] As mentioned above and in one configuration, the "circuits" may be implemented in machine-readable medium for execution by one or more of various types of processors, such as the processor 204 of FIG. 3. Executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the circuit and achieve the stated purpose for the circuit. Indeed, a circuit of computer readable program code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within circuits, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network.

[0115] While the term "processor" is briefly defined above, the term "processor" and "processing circuit" are meant to be broadly interpreted. In this regard and as mentioned above, the "processor" may be implemented as one or more processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components structured to execute instructions provided by memory. The one or more processors may take the form of a single core processor, multi-core processor (e.g., a dual core processor, triple core processor, quad core processor, etc.), microprocessor, etc. In some embodiments, the one or more processors may be external to the apparatus, for example the one or more processors may be a remote processor (e.g., a cloud based processor). Alternatively or additionally, the one or more processors may be internal and / or local to the apparatus. In this regard, a given circuit or components thereof may be disposed locally (e.g., as part of a local server, a local computing system, etc.) or remotely (e.g., as part of a remote server such as a cloud based server). To that end, a "circuit" as described herein may include components that are distributed across one or more locations.

[0116] Embodiments within the scope of the present disclosure include program products comprising computer or machine-readable media for carrying or having computer or machine-executable instructions or data structures stored thereon. Such machine-readable media can be any available media that can be accessed by a computer. The computer readable medium may be a tangible computer readable storage medium storing the computer readable program code. The computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable medium may include but are not limited to a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), an optical storage device, a magnetic storage device, a holographic storage medium, a micromechanical storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, and / or store computer readable program code for use by and / or in connection with an instruction execution system, apparatus, or device. Machine-executable instructions include, for example, instructions and data which cause a computer or processing machine to perform a certain function or group of functions.

[0117] The computer readable medium may also be a computer readable signal medium. A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electrical, electro-magnetic, magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport computer readable program code for use by or in connection with an instruction execution system, apparatus, or device. Computer readable program code embodied on a computer readable signal medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, Radio Frequency (RF), or the like, or any suitable combination of the foregoing.

[0118] In one embodiment, the computer readable medium may comprise a combination of one or more computer readable storage mediums and one or more computer readable signal mediums. For example, computer readable program code may be both propagated as an electro-magnetic signal through a fiber optic cable for execution by a processor and stored on RAM storage device for execution by the processor.

[0119] Computer readable program code for carrying out operations for aspects of the present disclosure may be written in any combination of one or more other programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone computer-readable package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0120] The program code may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function / act specified in the schematic flowchart diagrams and / or schematic block diagrams block or blocks.

[0121] Although the figures and description may illustrate a specific order of method steps, the order of such steps may differ from what is depicted and described, unless specified differently above. Also, two or more steps may be performed concurrently or with partial concurrence, unless specified differently above. Such variation may depend, for example, on the software and hardware systems chosen and on designer choice. All such variations are within the scope of the disclosure. Likewise, software implementations of the described methods could be accomplished with standard programming techniques with rule-based logic and other logic to accomplish the various connection steps, processing steps, comparison steps, and decision steps.

[0122] It is important to note that the construction and arrangement of the apparatus and system as shown in the various exemplary embodiments is illustrative only. Additionally, any element disclosed in one embodiment may be incorporated or utilized with any other embodiment disclosed herein.

Examples

Embodiment Construction

[0025] FIG. 1 is a block diagram of an engine system, according to an example embodiment. FIG. 2 is a block diagram of a controller of the system of FIG. 1, according to an example embodiment. FIG. 3 is a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4A is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 4B is a portion of a flow diagram of a method of determining the presence of biodiesel in the system of FIG. 1, according to an example embodiment. FIG. 5 is an illustration of a graph depicting a temperature deficit over time, according to an example embodiment.

DETAILED DESCRIPTION

[0026]Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, computer-readable media, and systems for detecting biodiesel in a fuel system of an internal ...

Claims

1. A method of determining a presence of biodiesel in a fuel system comprising: receiving, by at least one processor, one or more enable conditions regarding at least one of an engine system coupled to the fuel system or an aftertreatment system coupled to the engine system; and responsive to receiving the one or more enable conditions, executing an exotherm logic by the at least one processor to perform operations comprising: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component, based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of the presence of biodiesel in the fuel system.

2. The method of claim 1, wherein the exotherm logic is executed by the at least one processor to perform further operations comprising: responsive to enabling the biodiesel detection flag, incrementing a biodiesel detection counter value; and responsive to the biodiesel detection counter value being at or above a predetermined biodiesel detection counter threshold, generating the indication of the presence of biodiesel in the fuel system.

3. A system comprising: a controller coupled to an engine, a fuel system, and an aftertreatment system, the controller comprising one or more processors and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: receiving one or more enable conditions regarding at least one of the engine, the fuel system, or the aftertreatment system; and responsive to receiving the one or more enable conditions: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of a presence of biodiesel in the fuel system.

4. The method of claim 1, wherein the exotherm logic is executed by the at least one processor to perform further operations comprising, or the system of claim 3, wherein responsive to receiving the one or more enable conditions, the operations further comprise: receiving a fueling value regarding a regeneration event; and responsive to determining that the fueling value is at or above a fourth predefined threshold, enabling a third flag, wherein the biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

5. The method of claim 1, wherein the exotherm logic is executed by the at least one processor to perform further operations comprising, or the system of claim 3, wherein responsive to receiving the one or more enable conditions, the operations further comprise: enabling a third flag responsive to determining that the first temperature is at or below a fourth predefined threshold, wherein the biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

6. The method of claim 1, wherein the exotherm logic is executed by the at least one processor to perform further operations comprising, or the system of claim 3, wherein responsive to receiving the one or more enable conditions, the operations further comprise: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a fourth predefined threshold; and responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold, enabling a third flag, wherein the biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

7. The method of claim 1, wherein the exotherm logic is executed by the at least one processor to perform further operations comprising, or the system of claim 3, wherein responsive to receiving the one or more enable conditions, the operations further comprise: receiving a regeneration event stage of a regeneration event; and responsive to the regeneration event stage being during or after a predefined regeneration stage, enabling a third flag, wherein the biodiesel detection flag is enabled responsive to enabling the first flag, the second flag, and the third flag.

8. The method of claim 1, or the system of claim 3, wherein receiving the one or more enable conditions comprises receiving an indication of an amount of time that the first component of the aftertreatment system has been operating is at or below a fourth predefined threshold.

9. The method of claim 1, or the system of claim 3, wherein receiving the one or more enable conditions comprises receiving an indication that an efficiency value of the first component is at or above a predefined threshold.

10. The system of claim 3, wherein receiving the one or more enable conditions comprises receiving a regeneration event trigger indicative of one or more conditions that trigger a regeneration event including at least one of a duration since a most recent regeneration event elapsing, a pressure value regarding a second component of the aftertreatment system being at or above a predefined pressure threshold, or a user input.

11. A system comprising: an aftertreatment system coupled to an engine; and a controller coupled to the engine, a fuel system, and the aftertreatment system, the controller comprising one or more processors and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: receiving one or more enable conditions regarding at least one of the engine, the fuel system, or the aftertreatment system; and responsive to receiving the one or more enable conditions: receiving a first temperature regarding an inlet of a first component of the aftertreatment system and a second temperature regarding an outlet of the first component; determining an actual exotherm value regarding the first component based on the first temperature and the second temperature; responsive to the actual exotherm value being at or below a first predefined threshold during a predefined duration, incrementing a counter value; responsive the counter value being at or above a second predefined threshold, enabling a first flag; receiving an expected temperature regarding the outlet of the first component; determining an expected exotherm value regarding the first component, based on the first temperature and the expected temperature; responsive to a difference between the expected exotherm value and the actual exotherm value being at or below a third predefined threshold, enabling a second flag; responsive to enabling at least the first flag and the second flag, enabling a biodiesel detection flag; and generating an indication of a presence of biodiesel in the fuel system.

12. The system of claim 11, wherein responsive to receiving the one or more enable conditions, the operations further comprise: receiving a fueling value regarding a regeneration event; enabling a third flag responsive to determining that the fueling value is at or above a fourth predefined threshold; and enabling a fourth flag responsive to determining that the first temperature is at or below a fifth predefined threshold.

13. The system of claim 12, wherein responsive to receiving the one or more enable conditions, the operations further comprise: receiving a rate of change of a regeneration event duration, responsive to the first temperature being at or above a sixth predefined threshold; enabling a fifth flag responsive to the rate of change of the regeneration event duration being at or below a predefined rate of change threshold; receiving a regeneration event stage of a regeneration event; and enabling a sixth flag responsive to the regeneration event stage being during or after a predefined regeneration stage.

14. The system of claim 13, wherein responsive to receiving the one or more enable conditions, the operations further comprise enabling the biodiesel detection flag responsive to enabling at least the first flag, the second flag, the third flag, the fourth flag, the fifth flag, and the sixth flag.

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