Heating system for diesel exhaust fluid tanks

Abstract

The systems and apparatus include a diesel exhaust fluid tank, a first temperature sensor positioned within the diesel exhaust fluid tank and configured to provide first temperature information indicative of a first temperature, and a second temperature sensor positioned within the diesel exhaust fluid tank and configured to provide second temperature information indicative of a second temperature. The systems and apparatus further include one or more processing circuits including one or more memory devices coupled to the one or more processors, the one or more memory devices configured to store instructions that, when executed by the one or more processors, cause the one or more processors to provide energy to a heating system based on the first temperature information and the second temperature information. TIFF2023550686000002.tif88128

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 104,848, filed October 23, 2020, the entire contents of which are incorporated herein by reference.

[0002] Technical Field The present disclosure relates to engine exhaust aftertreatment systems, and more particularly, to systems and methods for diesel exhaust fluid (DEF) management in selective catalytic reduction (SCR) aftertreatment systems. [Background technology]

[0003] background SCR aftertreatment systems consume diesel exhaust fluid (DEF), which typically contains 32.5% urea and 67.5% deionized water. Typically, DEF freezes at minus 12 degrees Celsius (-12°C) or 11 degrees Fahrenheit (11°F). Summary of the Invention

[0004] overview In one aspect, a diesel exhaust fluid tank; a first temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide first temperature information indicative of a first temperature; a second temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide second temperature information indicative of a second temperature; and One or more processing circuits including one or more memory devices coupled to one or more processors, the one or more memory devices comprising: instructions that, when executed by the one or more processors, cause the one or more processors to provide energy to the heating system based on the first temperature information and the second temperature information. one or more processing circuits configured to store The present invention relates to a diesel exhaust fluid system, including:

[0005] Another aspect relates to a diesel exhaust fluid tank control system for use with a diesel exhaust fluid tank including a temperature ultrasonic level and concentration (TULC) sensor and a heating system. The diesel exhaust fluid tank control system comprises: a temperature sensor array positioned within the diesel exhaust fluid tank and constructed to provide temperature information; One or more processing circuits including one or more memory devices coupled to one or more processors, the one or more memory devices comprising: instructions that, when executed by the one or more processors, cause the one or more processors to provide energy to a heating system based on the temperature information. one or more processing circuits configured to store Includes.

[0006] Another aspect relates to a method that includes receiving primary temperature information indicative of a primary temperature from a first temperature sensor positioned within the diesel exhaust fluid tank, receiving secondary temperature information indicative of a secondary temperature from a temperature sensor array positioned within the diesel exhaust fluid tank, and selectively providing energy to a heating system positioned within the diesel exhaust fluid tank based on the primary temperature and the secondary temperature.

[0007] This summary is merely illustrative and is in no way intended to be limiting. Other aspects, inventive features, and advantages of the devices or processes described herein will become apparent in the detailed description set forth herein, taken in conjunction with the accompanying figures, in which like reference numerals refer to like elements and in which: [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a DEF heating system according to some embodiments. [Diagram 2] FIG. 2 is a cross-sectional view of a DEF tank according to some embodiments. [Diagram 3] FIG. 3 is a schematic diagram of a DEF heating system according to some embodiments. [Figure 4] FIG. 4 is a schematic diagram of a DEF heating system according to some embodiments. [Diagram 5] FIG. 5 is a schematic diagram of a controller for a DEF heating system according to some embodiments. [Figure 6] FIG. 6 is a flow diagram of a method of operating a DEF heating system according to some embodiments. [Figure 7] 7A-D are schematic diagrams of a DEF heating system according to some embodiments. [Figure 8] 8A-D are schematic diagrams of a DEF heating system according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Detailed Description A more detailed description of various concepts related to methods, apparatus, and systems for thawing a diesel exhaust fluid (DEF) tank, as well as embodiments of those methods, apparatus, and systems, follows below. Before referring now to the figures, which illustrate in detail certain exemplary embodiments, it should be understood that the disclosure is not limited to the details or methods set forth in the description or illustrated in the figures. It should also be understood that the terminology used herein is merely descriptive and should not be considered limiting.

[0010] A typical diesel exhaust fluid (DEF) anti-freeze system utilizes a temperature and ultrasonic liquid level and concentration (TULC) sensor that includes a single temperature sensor located inside the DEF tank or container. The TULC sensor provides localized defrosting capabilities because the temperature is measured only at a single point in the DEF tank and may not represent a uniform temperature throughout the DEF in the DEF tank. For example, off-highway vehicles such as mining trucks may have large engines (e.g., over 700 horsepower) and DEF tanks larger than 30, 60, 100, and 200 gallon tanks. In large DEF tanks, the local temperature measured by the TULC sensor does not necessarily represent the DEF temperature throughout the DEF tank, especially at low temperatures (e.g., 0 degrees Fahrenheit). As previously mentioned, typically, DEF freezes at minus 12 degrees Celsius (-12°C) or 11 degrees Fahrenheit (11°F).

[0011] In a typical system, the temperature signal from the TULC sensor is used to activate a heat source that is applied to the DEF tank and other emissions-related components. Accurate measurements are critical to ensure emissions regulations are met.

[0012] Referring generally to the figures, various aspects disclosed herein relate to a system, apparatus, and method for improved thawing of a DEF tank. The DEF heating or thawing system includes a controller (e.g., an engine control module or a dedicated controller) that controls an electronically controlled coolant valve that selectively provides heated coolant from an engine to a heat exchanger positioned in the DEF tank to heat or thaw the DEF in the tank when the temperature of the DEF in the DEF tank is at or below a predetermined temperature (e.g., 15 degrees Celsius). The controller receives temperature information from a TULC sensor located adjacent to the heat exchanger and a secondary temperature sensor array including one or more temperature sensors spaced apart from the TULC sensor and positioned in the DEF tank. The secondary temperature sensor array, calibrated to the TULC sensor, post-processes all temperature signals and creates a temperature matrix that is used to provide a more accurate heating strategy and / or control of the DEF heating system. A temperature matrix can be created using pre-programmed models, algorithms, logic, or machine learning methods to provide a more accurate thermal model of the DEF in the DEF tank, which in turn provides more accurate control of the electronically controlled coolant valve to better maintain the temperature in the DEF tank or thaw the DEF in the DEF tank. The improved DEF heating system provides benefits including elimination of hot spots near the TULC sensor that can cause the coolant flow to the heat exchanger to be prematurely shut off, thereby leaving some DEF frozen in the DEF tank. Another benefit of a more accurate thermal model is that it eliminates false indications of the amount of thawed DEF ready to be injected. The thermal model allows the aftertreatment system to better initiate dosing sooner.

[0013] As shown in FIG. 1 , a diesel exhaust fluid system in the form of a DEF heating system 10 includes an engine 14, a DEF tank 18, and a switching element in the form of an electronically controlled coolant valve 22 that controls the flow of energy to the DEF tank 18 to heat the DEF held within the DEF tank 18. In some embodiments, the switching element includes an electronic switch, a mechanically operated valve, or other switching device. In some embodiments, the energy to heat the DEF tank 18 is provided by a generator, a battery, an auxiliary heating system, or another heat source other than the engine 14. Generally, the engine 14 generates heat that is absorbed by the coolant. The electronically controlled coolant valve 22 controls the flow of coolant to the DEF tank 18 to heat the DEF tank.

[0014] As shown in FIG. 2, the DEF tank 18 includes a header 26 constructed to enclose the DEF tank 18 and support a filter, suction and fill lines for the DEF, a heating unit 30 including a heating element in the form of a heat exchanger 34, and a TULC sensor 38. In some embodiments, the heating element is a submersible resistive heating element or another heating element as desired. The header 26 includes two heating units 30, 30' that are substantially identical. In some embodiments, more than two or less than two heating units 30 are included in the header 26. The heat exchanger 34 is fluidly coupled to the electronically controlled coolant valve 22 and selectively receives the coolant heated by the engine 14. The heat exchanger 34 exchanges heat between the DEF held in the DEF tank 18 and the coolant heated by the engine 14.

[0015] As shown in FIG. 3, the TULC sensor 38 is centrally located within the DEF tank 18. The DEF heating system 10 also includes a secondary sensor array 42 including a first temperature sensor 46, a second temperature sensor 50, a third temperature sensor 54, and a fourth temperature sensor 58. In some embodiments, the TULC sensor 38 includes a group of sensors including a level sensor, a quality sensor, and a first temperature sensor. In some embodiments, the secondary sensor array 42 includes more than four temperature sensors or fewer than four temperature sensors. For example, a 30 gallon DEF tank may require one temperature sensor in the secondary sensor array 42, while a 100 gallon DEF tank may require five temperature sensors in the secondary sensor array 42. The secondary sensor array 42 is positioned to sense the temperature of the DEF within the DEF tank 18 at a location away from the TULC sensor 38. For example, corners of a large DEF tank 18 may not experience as much thermal cycling and may not heat evenly along with the bulk of the DEF within the DEF tank 18. The secondary sensor array 42 may have temperature sensors positioned at remote corners to provide the temperature at the corners. As shown in Figure 3, four temperature sensors 46, 50, 54, 58 are positioned at the four corners of the generally rectangular DEF tank 18.

[0016] The TULC sensor 38 is communicatively coupled to an engine control module (ECM) 62 associated with the engine 14. The secondary sensor array 42 is coupled to a diesel exhaust fluid tank control system in the form of a controller 66 that communicates with the ECM 62. In some aspects, the controller 66 is mounted on the engine 14. In some aspects, the controller 66 is mounted remotely from the engine 14. The ECM 62 and the controller 66 coordinate and develop a thermal model of the DEF tank 18. In some aspects, the controller 66 is embodied as a module or circuit within the ECM 62. In some aspects, the controller 66 is a separate controller located remotely from the ECM 62. In some aspects, the ECM 62 and the controller 66 are shared, distributed, or combined in a cloud-based control manner.

[0017] 4, the TULC sensor 38 and secondary sensor array 42 may communicate directly with the controller 66, which may communicate with the ECM 62 to effectuate control of the electronically controlled coolant valve 22. In some aspects, the controller 66 communicates directly with the electronically controlled coolant valve 22 without intervention of the ECM 62.

[0018] 1 are shown embodied in a vehicle including the DEF heating system 10, the controller 66 may be constructed as one or more electronic control units (ECUs). The controller 66 may be separate from or included in at least one of a transmission control unit, an exhaust aftertreatment control unit, a powertrain control module, an engine control module (e.g., ECM 62), etc. The function and structure of the controller 66 are described in more detail in FIG.

[0019] 5, a schematic diagram of the controller 66 of the DEF heating system 10 of FIG. 1 is shown, according to an exemplary embodiment. As shown in FIG. 5, the controller 66 includes a processing circuit 70 having a processor 74 and a memory device 78, a control system 80 having a sensor circuit 84, an ECM circuit 88, a modeling engine 92, and a heating circuit 96, and a communication interface 100. In general, the controller 66 is configured to generate a thermal model of the DEF tank 18 and control the operation of the electronically controlled coolant valve 22.

[0020] In one configuration, the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 are embodied as a machine-readable or computer-readable medium executable by a processor, such as the processor 74. The machine-readable medium facilitates the performance of certain operations to enable, among other uses, the transmission and reception of data, as described herein. For example, the machine-readable medium may provide instructions (e.g., instructions, etc.) for, for example, acquiring data. In this regard, the machine-readable medium may include programmable logic that defines the frequency of acquiring (or transmitting) data. The computer-readable medium may include code, which may be written in any programming language, including, but not limited to, Java, and any conventional procedural programming language, such as the "C" programming language or similar programming language. The computer-readable program code may be executed on one processor or on multiple remote processors. In the latter scenario, the remote processors may be connected to each other via any type of network (e.g., a CAN bus, etc.).

[0021] In another configuration, the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 are embodied as a hardware unit, such as an electronic control unit. As such, the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may be embodied as one or more circuit components, including, but not limited to, processing circuits, network interfaces, peripheral devices, input devices, output devices, sensors, and the like. In some embodiments, the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (ICs), discrete circuits, system-on-a-chip (SOC) circuits, microcomputers, etc.), communication circuits, hybrid circuits, and any other type of "circuitry." In this regard, the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may include any type of components for implementing or facilitating the accomplishment of the operations described herein. For example, the circuits 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, etc. The sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may also include programmable hardware devices, such as field programmable gate arrays, programmable array logic, programmable logic devices, etc. The sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may include one or more memory devices for storing instructions executable by the processors of the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96. The one or more memory devices and processors may have the same definitions as given below with respect to the memory device 78 and the processor 74. In some hardware unit configurations, the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may be geographically distributed throughout separate locations within the vehicle.Alternatively, as shown, the sensor circuitry 84 , ECM circuitry 88 , modeling engine 92 , and heating circuitry 96 may be embodied in or within a single unit / enclosure, shown as controller 66 .

[0022] In the illustrated example, the controller 66 includes a processing circuit 70 having a processor 74 and a memory device 78. The processing circuit 70 may be constructed or configured to execute or implement the instructions, commands, and / or control processes described herein with respect to the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96. The depicted configuration represents the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 as machine-readable or computer-readable media. However, this example is not intended to be limiting, as, as noted above, the disclosure also contemplates other aspects in which the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96, or at least one of the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96, are configured as a single hardware unit. All such combinations and variations are intended to be within the scope of the present disclosure.

[0023] The hardware and data processing components (e.g., processor 74) used to implement the various processes, operations, example logic, logic blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented or embodied with general purpose single-chip or multi-chip processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, or any conventional processor, or state machine. A processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In some embodiments, one or more processors may be shared by multiple circuits (e.g., the sensor circuitry 84, the ECM circuitry 88, the modeling engine 92, and the heating circuitry 96 may include or otherwise share the same processor, which in some exemplary embodiments may execute instructions stored or otherwise accessed by different regions of memory). Alternatively or additionally, one or more processors may be configured to perform or otherwise execute certain operations independently of one or more coprocessors. In other exemplary embodiments, two or more processors may be coupled via buses to enable independent, parallel, pipelined, or multi-threaded instruction execution. All such variations are intended to be within the scope of the present disclosure.

[0024] The memory device 78 (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 this disclosure. The memory device 78 may be communicatively connected to the processor 74 for providing computer code or instructions to the processor 74 for executing at least some of the processes described herein. Moreover, the memory device 78 may be or include tangible non-transitory volatile or non-volatile memory. Thus, the memory device 78 may include database components, object code components, script components, or any other type of information structures for supporting the various activities and information structures described herein.

[0025] The sensor circuitry 84 is constructed to collect temperature information from the TULC sensor 38 and the secondary sensor array 42 via the communications interface 100. In some embodiments, the sensor circuitry 84 manipulates the information provided by the TULC sensor 38 and the secondary sensor array 42 for use by the controller 66. For example, the sensor circuitry 84 may average the temperature information of the individual sensors (e.g., temperature sensors 46, 50, 54, 58), process the temperature information in a weighted average, or perform other processing.

[0026] The ECM circuit 88 is constructed to communicate with the ECM 62 to coordinate operation therewith. In some embodiments, the ECM circuit 88 is the ECM 62. In some embodiments, the ECM circuit 88 controls operation of the electronically controlled coolant valve 22 by providing communication with the ECM 62 via a communication interface 100. In some embodiments, the sensor circuit 84 does not communicate directly with the TULC sensor 38, and temperature information from the TULC sensor 38 is received by the ECM circuit 88.

[0027] The modeling engine 92 is configured to generate a thermal model of the DEF tank 18 based on the temperature information received from the sensor circuitry 84 and the ECM circuitry 88. In some aspects, the thermal model includes machine learning methods (reinforcement learning, neural networks, etc.) that learn the relationship between the TULC sensor 38 and the secondary sensor array to generate a three-dimensional heat map of the DEF tank 18 to determine where in the DEF tank 18 the DEF is above a predetermined threshold temperature and where in the DEF tank 18 the DEF is below the threshold temperature. In some aspects, the thermal model is based on pre-programmed models, algorithms, ladder logic, etc.

[0028] In some embodiments, the temperature indicated by the TULC sensor 38 is a primary temperature T1, and the temperature indicated by the secondary sensor array 42 is a secondary temperature T2. In some embodiments, each individual sensor in the secondary sensor array 42 is assigned a temperature (e.g., T2-T5). The modeling engine 92 then compares the primary temperature T1 with the secondary temperature T2 or all of the secondary temperatures T2-T5 and returns the lowest temperature for use by the controller 66. For example, if the secondary temperature T2 is lower than the primary temperature T1, the thermal model returns the secondary temperature. In some embodiments, a weighted average is assigned to the temperatures T1-T5 such that the sensors are given priority. For example, the primary temperature T1 determined by the TULC sensor 38 may be the temperature with the highest priority. The modeling engine 92 may assign a predetermined range within which the primary temperature is returned. For example, if the threshold temperature is fifteen degrees Celsius (15° C.) and the range is one degree Celsius (1° C.), then the secondary temperature is returned when the secondary temperature is equal to or less than fourteen degrees Celsius (14° C.).

[0029] The heating circuit 96 receives the thermal model and communicates with the electronically controlled coolant valve 22 to operate the electronically controlled coolant valve 22 between an open position in which coolant is provided to the heat exchanger 34 and a closed position in which coolant is prevented from flowing to the heat exchanger 34. In some embodiments, the electronically controlled coolant valve 22 is closed when the thermal model indicates that the temperature of the DEF in the DEF tank 18 is equal to or greater than a threshold temperature (e.g., 15° C.) and is open when the thermal model indicates that the temperature of the DEF in the DEF tank 18 is less than the threshold temperature (e.g., 15° C.). In some embodiments, the heating circuit 96 communicates with the ECM 62 via a communication interface 100 to effectuate control of the electronically controlled coolant valve 22.

[0030] 6, a method 104 of operating the DEF heating system 10 includes receiving a primary temperature T1 from the TULC sensor 38 at step 108 and a secondary temperature T2 from the secondary sensor array 42 at step 112. The controller 66 then generates a thermal model at step 116. In some aspects, the thermal model generated at step 116 is used directly (e.g., via a three-dimensional heat map) to determine parameters of the DEF (e.g., percentage and distribution of melted DEF, volume of melted DEF, temperature distribution, etc.), and the thermal model is used directly to determine operation of the electronically controlled coolant valve 22.

[0031] As shown in FIG. 6, the controller 66 compares the first temperature and the second temperature in step 120. If the first temperature T1 is less than or equal to the second temperature T2, the method 104 proceeds to step 124 where the first temperature T1 is compared to a threshold temperature (e.g., 15° C.). If the first temperature T1 is less than (or equal to) the threshold temperature, the diesel exhaust fluid (DEF) pump cannot yet be primed and the DEF tank 18 must be thawed. In step 128, the electronically controlled coolant valve 22 is opened to heat the DEF in the DEF tank 18, and the method returns to steps 108 and 112. If the first temperature T1 is greater than (or equal to) the threshold temperature in step 124, the method 104 proceeds to step 132 where the controller 66 compares the second temperature T2 to the threshold temperature. If the second temperature T2 is greater than (or equal to) the threshold temperature, the DEF pump is primed in step 136. If the secondary temperature T2 is less than (or equal to) the threshold temperature in step 132, the electronically controlled coolant valve 22 is opened to further heat the DEF. In some aspects, step 132 is omitted.

[0032] If the secondary temperature T2 is less than the primary temperature T1 at step 120, the method 104 proceeds to step 140 where the secondary temperature T2 is compared to a threshold temperature. If the secondary temperature T2 is less than (or equal to) the threshold temperature, the electronically controlled coolant valve 22 is opened at step 128, and if the secondary temperature T2 is greater than (or equal to) the threshold temperature, the DEF pump is primed at step 136.

[0033] The systems and methods described above advantageously provide improved control of the thawing and heating of DEF in larger DEF tanks, which is particularly important in DEF tanks 18 larger than 30 gallon tanks, for example, where cool spots tend to exist where existing systems erroneously indicate the temperature of the DEF throughout the DEF tank 18.

[0034] As shown in FIGS. 7A-7D, the DEF tank 18 including the first heating unit 30 and the second heating unit 30' can be arranged in an opposing direction with the secondary sensors 46 and 50 located away from the heat exchangers 34 and 34'. The location of the TULC 38 is approximately centrally located within the DEF tank 18 to reduce the effects of sloshing of the DEF within the DEF tank 18. However, the central location of the TULC 38 can lead to an inaccurate assessment of the state of the DEF within the DEF tank 18 without the addition of a secondary sensor array 42 including the secondary sensors 46 and 50. FIGS. 8A-8D show another embodiment of a DEF tank 18 including two heating units 30 and 30' arranged approximately parallel and facing in the same direction. In some embodiments, the DEF tank arrangement shown in FIGS. 7A-7D and 8A-8D can include only one secondary sensor 46 or three or more secondary sensors. The heat exchangers 34, 34' are positioned in separate portions of the DEF tank 18 to provide heat to separate regions, volumes, or portions of the DEF tank 18 to more uniformly thaw the DEF in the DEF tank 18. The separate portions of the DEF tank 18 do not overlap. The heat exchangers 34, 34' are positioned in the separate portions so that they do not overlap. In some embodiments, a first heating element including the heat exchanger 34 is positioned in a first portion of the diesel exhaust fluid tank 18 and a second heating element including the heat exchanger 34' is positioned in a second portion of the diesel exhaust fluid tank 18 that does not overlap the first portion.

[0035] As used herein, the terms "approximately," "about," "substantially," and similar terms are intended to have broad meanings consistent with common and accepted usage by those of ordinary skill in the art to which the subject matter of the present disclosure pertains. It should be understood by those of ordinary skill in the art who review this disclosure that these terms are intended to enable the description of the particular features described and claimed without limiting the scope of these features to the precise numerical ranges provided. Thus, these terms should be interpreted to indicate that insubstantial or insignificant modifications or variations of the subject matter described and claimed are considered to be within the scope of the disclosure as set forth in the appended claims.

[0036] It should be noted that, when used herein to describe various embodiments, the term "exemplary" and variations thereof are intended to indicate that such embodiments are possible examples, representations, or illustrations of possible embodiments (nor are such terms intended to imply that such embodiments are necessarily particular or best examples).

[0037] As used herein, the term "coupled" and variations thereof mean that two members are joined directly or indirectly to each other. Such joining can be static (e.g., permanent or fixed) or movable (e.g., removable or releasable). Such joining can be achieved by two members directly joined to each other, by two members joined to each other using one or more separate intermediate members, or by two members joined to each other using an intermediate member integrally formed as a single unit with one of the two members. When "coupled" or variations thereof are modified by an additional term (e.g., directly coupled), the general definition of "coupled" provided above is modified by the plain language meaning of the additional term (e.g., "directly coupled" means joining of two members without any separate intermediate members), resulting in a definition narrower than the general definition of "coupled" provided above. Such joining can be mechanical, electrical, or fluid. For example, circuit A being communicatively "coupled" to circuit B may mean that circuit A communicates directly with circuit B (i.e., without any intermediary means) or indirectly with circuit B (e.g., via one or more intermediary means).

[0038] References herein to the location of elements (e.g., "top", "bottom", "upper", "lower", etc.) are used merely to describe the orientation of various elements in the figures. It should be noted that the orientation of various elements may vary according to other exemplary embodiments, and such variations are intended to be encompassed by the present disclosure.

[0039] Although various circuits with specific functions are shown in FIG. 5, it should be understood that the controller 66 may include any number of circuits to complete the functions described herein. For example, the activities and functions of the sensor circuit 84, the ECM circuit 88, the modeling engine 92, and the heating circuit 96 may be combined in multiple circuits or as a single circuit. Additional circuits with additional functions may also be included. Moreover, the controller 66 may further control other activities beyond the scope of this disclosure.

[0040] As mentioned above, in one configuration, a "circuit" may be implemented in a machine-readable medium for execution by various types of processors, such as processor 74 of FIG. 5. A specified circuit of executable code may include, for example, one or more physical or logical blocks of computer instructions, which may be organized as, for example, an object, procedure, or function. Nevertheless, the executable code of a specified circuit may include entirely different instructions stored in different locations that, when logically coupled to one another, comprise the circuit and achieve the above-mentioned purpose of the circuit. In fact, a circuit of computer-readable program code may be a single instruction, or many instructions, and may even be distributed across several different code segments, among several different programs, and across several memory devices. Similarly, operational data may be specified and illustrated in a circuit herein, and may be embodied in any suitable form and organized in any suitable type of data structure. The operational data may be collected as a single data set or distributed in different locations, including different storage devices, and may exist, at least in part, simply as electronic signals on a system or network.

[0041] The term "processor" is briefly defined above, however, the terms "processor" and "processing circuitry" are intended to be interpreted broadly. In this regard, as discussed above, a "processor" may be implemented as one or more general-purpose processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components configured to execute instructions provided by a memory. The one or more processors may take the form of a single-core processor, a multi-core processor (e.g., a dual-core processor, a triple-core processor, a quad-core processor, etc.), a microprocessor, etc. In some aspects, the one or more processors may be external to the device, e.g., the one or more processors may be remote processors (e.g., cloud-based processors). Alternatively or additionally, the one or more processors may be internal and / or local to the device. In this regard, a given circuit or component may be located 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 distributed throughout one or more locations.

[0042] Aspects within the scope of the present disclosure include program products that include machine-readable media for holding or having stored thereon machine-executable instructions or data structures. Such machine-readable media can be any available media that can be accessed by a general purpose or special purpose computer or other machine with a processor. By way of example, such machine-readable media can include RAM, ROM, EPROM, EEPROM, or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to hold or store desired program code in the form of machine-executable instructions or data structures and that can be accessed by a general purpose or special purpose computer or other machine with a processor. Combinations of the above are also included within the scope of machine-readable media. Machine-executable instructions include, for example, instructions and data that cause a general purpose computer, special purpose computer, or special purpose processing machine to perform a certain function or group of functions.

[0043] Although the figures and description may show a particular order of method steps, the order of such steps may differ from that depicted and described unless otherwise specified above. Also, two or more steps may be performed simultaneously or with partial concurrence unless otherwise specified above. Such variations may depend, for example, on the selected software and hardware systems and on the designer's choice. All such variations are within the scope of this disclosure. Similarly, software implementations of the described methods may be realized using standard programming techniques using rule-based and other logic to realize the various connection, processing, comparison, and decision steps.

[0044] It is important to note that the configurations and arrangements of the DEF heating system 10 shown in the various exemplary embodiments are merely exemplary. Additionally, any element disclosed in one embodiment may be combined or utilized with any other embodiment disclosed herein. For example, the controller 66 of the exemplary embodiment may be incorporated into the ECM 62 of the exemplary embodiment. Although only one example of elements of one embodiment that may be combined or utilized in another embodiment has been described above, it should be understood that other elements of the various embodiments may be combined or utilized with any of the other embodiments disclosed herein.

Claims

1. a diesel exhaust fluid tank; a first temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide first temperature information indicative of a first temperature; a second temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide second temperature information indicative of a second temperature; and One or more processing circuits including one or more memory devices coupled to one or more processors, the one or more memory devices comprising: When executed by the one or more processors, generating a three-dimensional heat map based on the first temperature information and the second temperature information; providing energy to a heating system having a heating element positioned in the diesel exhaust fluid tank to heat diesel exhaust fluid in the diesel exhaust fluid tank based on the three-dimensional heat map; 5. The method of claim 1, further comprising the steps of: the one or more processing circuits configured to store 1. A diesel exhaust fluid system comprising:

2. The diesel exhaust fluid system of claim 1 , wherein the one or more processing circuits further include an engine control module configured to receive the first temperature information.

3. the one or more memory devices: When executed by the one or more processors, generating a thermal model of the diesel exhaust fluid tank including the three-dimensional heat map; 5. The method of claim 1, further comprising the steps of: and further configured to store providing energy to the heating system when the thermal model indicates that the diesel exhaust fluid in the diesel exhaust fluid tank is below a predetermined threshold; 10. The diesel exhaust fluid system of claim 1.

4. the one or more memory devices: instructions that, when executed by the one or more processors, cause the one or more processors to provide energy to the heating element when: (i) the first temperature is less than or equal to a predetermined threshold and less than or equal to the second temperature; or (ii) the second temperature is less than or equal to the predetermined threshold and less than or equal to the first temperature. The diesel exhaust fluid system of claim 1 , further configured to store:

5. 10. The diesel exhaust fluid system of claim 1, wherein the diesel exhaust fluid tank is 30 gallons or larger.

6. further comprising an exhaust fluid tank header; the exhaust fluid tank header supporting each of the heating system, the first temperature sensor, and the second temperature sensor; 10. The diesel exhaust fluid system of claim 1.

7. The diesel exhaust fluid system of claim 1 further comprising a sensor group including a level sensor, a concentration sensor, and a first temperature sensor.

8. a third temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide third temperature information indicative of a third temperature; and a fourth temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide fourth temperature information indicative of a fourth temperature; a fifth temperature sensor positioned within the diesel exhaust fluid tank and constructed to provide fifth temperature information indicative of a fifth temperature; The diesel exhaust fluid system of claim 7 further comprising:

9. the one or more processing circuits further comprising an engine control module configured to receive the first temperature information from the group of sensors; the one or more memory devices: When executed by the one or more processors, receiving the first temperature information from the engine control module; receiving the second temperature information from the second temperature sensor; receiving the third temperature information from the third temperature sensor; receiving the fourth temperature information from the fourth temperature sensor; receiving the fifth temperature information from the fifth temperature sensor; generating a thermal model of the diesel exhaust fluid tank based on the first temperature information, the second temperature information, the third temperature information, the fourth temperature information, and the fifth temperature information, the thermal model including the three-dimensional heat map; 5. The method of claim 1, further comprising the steps of: and further configured to store 9. The diesel exhaust fluid system of claim 8.

10. The diesel exhaust fluid system of claim 1 , further comprising a heating system, the heating system including the heating element.

11. The diesel exhaust fluid system of claim 10 , wherein the heating element comprises a heat exchanger configured to receive coolant from the engine.

12. the heating system further comprising: The heating system comprises: a first heating element positioned in a first portion of the diesel exhaust fluid tank; a second heating element positioned in a second portion of the diesel exhaust fluid tank that does not overlap the first portion; and 10. The diesel exhaust fluid system of claim 1, comprising:

13. the one or more memory devices: When executed by the one or more processors, comparing the first temperature to the second temperature; comparing the first temperature to a predetermined threshold; comparing the second temperature to the predetermined threshold; providing energy to the heating system when the first temperature is less than or equal to the second temperature and the first temperature is less than or equal to the predetermined threshold or when the second temperature is less than or equal to the predetermined threshold; 5. The method of claim 1, further comprising the steps of: The diesel exhaust fluid system of claim 1 , further configured to store:

14. the one or more memory devices: instructions that, when executed by the one or more processors, cause the one or more processors to send a signal to permit operation of a diesel exhaust fluid pump if the second temperature is below the predetermined threshold. The diesel exhaust fluid system of claim 13 , further configured to store:

15. the first temperature sensor is part of a temperature ultrasonic level and concentration (TULC) sensor and heating system; 10. The diesel exhaust fluid system of claim 1, wherein the second temperature sensor is part of a temperature sensor array positioned within the diesel exhaust fluid tank.

16. the one or more memory devices: When executed by the one or more processors, determining a secondary temperature based on the temperature information received from the temperature sensor array; transmitting a signal to permit operation of the diesel exhaust fluid pump when the secondary temperature is greater than a predetermined threshold; 5. The method of claim 1, further comprising the steps of:

20. The diesel exhaust fluid system of claim 15, further configured to store:

17. the one or more memory devices: When executed by the one or more processors, receiving TULC temperature information from the TULC sensor indicative of a TULC temperature; determining a secondary temperature based on the temperature information received from the temperature sensor array; comparing the TULC temperature to the secondary temperature; comparing the TULC temperature to a predetermined threshold; comparing the secondary temperature to the predetermined threshold; providing energy to the heating system when the TULC temperature is less than or equal to the secondary temperature and the TULC temperature is less than or equal to the predetermined threshold or when the secondary temperature is less than or equal to the predetermined threshold; 5. The method of claim 1, further comprising the steps of:

20. The diesel exhaust fluid tank control system of claim 15, further configured to store:

18. receiving primary temperature information indicative of a primary temperature from a first temperature sensor positioned within the diesel exhaust fluid tank; receiving secondary temperature information indicative of a secondary temperature from a temperature sensor array positioned within the diesel exhaust fluid tank; generating a three-dimensional heat map based on the primary temperature information and the secondary temperature information; selectively providing energy to a heating system having a heating element positioned in the diesel exhaust fluid tank to heat diesel exhaust fluid within the diesel exhaust fluid tank based on the three-dimensional heat map; A method comprising:

19. comparing the first temperature to the second temperature; comparing the primary temperature to a predetermined threshold; comparing the secondary temperature to the predetermined threshold; providing energy to the heating system when the first temperature is less than or equal to the second temperature and the first temperature is less than or equal to the predetermined threshold or when the second temperature is less than or equal to the predetermined threshold; 20. The method of claim 18, further comprising:

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