Fluid management system for a hydrogen fueled internal combustion engine and an aftertreatment system

Abstract

A system includes a controller communicably coupled to a hydrogen fueled internal combustion engine. The controller includes at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations. The operations include receiving an engine shutdown request and responsive to receiving the engine shutdown request, executing an engine shutdown procedure including causing the engine to continue to rotate for at least a predetermined number of rotations or at least a predetermined time period.

Description

FLUID MANAGEMENT SYSTEM FOR A HYDROGEN FUELEDINTERNAL COMBUSTION ENGINE AND AN AFTERTREATMENTSYSTEMCROSS-REFERENCE TO RELATED APPLICATION

[0001] This PCT Application claims the benefit and priority to U.S. Provisional Application No. 63 / 601,669 filed November 21, 2023, which is incorporated herein by reference in its entirety and for all purposes.TECHNICAL FIELD

[0002] The present disclosure relates to a fluid management system for a hydrogen fueled internal combustion engine system and / or an aftertreatment system that is configured to purge or enable purging a fluid from a hydrogen fueled internal combustion engine and / or an aftertreatment system coupled to an internal combustion engine system.BACKGROUND

[0003] A hydrogen fueled internal combustion engine consumes hydrogen fuel to produce power (e.g., for turning a crankshaft of a system embodying the engine, such as vehicle). Unlike internal combustion engines that burn carbonaceous fuel, such as diesel fuel or gasoline, the exhaust produced by a hydrogen internal combustion engine may not include hydrocarbons or carbon oxides (e.g., carbon monoxide or carbon dioxide). Rather, the exhaust may include sulfur oxides (SOx) originating from burning lubricants, nitrogen oxides (NOx) originating from burning the hydrogen fuel in the presence of air (including nitrogen, N2, and oxygen, O2), and / or water (H2O) originating from burning the hydrogen fuel in the presence of air (including oxygen, O2) or from the presence of water (e.g., humidity) in the intake air. The exhaust may also include unconsumed hydrogen (H2).SUMMARY[00041 One embodiment relates to a system. The system includes a controller communicably coupled to a hydrogen fueled internal combustion engine. The controller includes at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations. The operations include receiving an engine shutdown request; and responsive to receiving the engine shutdown request, executing an engine shutdown procedure comprising causing the engine to continue to rotate for at least a predetermined number of rotations or at least a predetermined time period.

[0005] Another embodiment relates to a system. The system includes a controller communicably coupled to an engine configured to combust hydrogen fuel and an electric machine coupled to the engine. The controller includes at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations. The operations include receiving information indicative of a hydrogen content value in the system; comparing the hydrogen content value to a threshold value; and responsive to determining that the hydrogen content value exceeds the threshold value, executing a fluid purge procedure including causing the electric machine to rotate the engine for at least a predetermined number of rotations or at least a predetermined time period.

[0006] Another embodiment relates to a system. The system includes a controller communicably coupled to an engine configured to combust hydrogen fuel and a compressed air system coupled to at least one of the engine or an air starter. The controller includes at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations. The operations include causing the compressed air system to rotate the engine for at least one of: a predetermined number of rotations, a predetermined time period, a predetermined number of combustion events, or until a speed of the engine exceeds a predetermined threshold.

[0007] Numerous specific details are provided to impart a thorough understanding of embodiments of the subject matter of the present disclosure. The described features of thesubject 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 OF THE DRAWINGS100081 FIG. l is a block diagram of a hydrogen fueled internal combustion engine system, according to an example embodiment.

[0009] FIG. 2 is a block diagram of a cylinder assembly of the engine system of FIG. 1, according to an example embodiment.

[0010] FIG. 3 is a block diagram of a controller of the system of FIG. 1, according to an example embodiment.

[0011] FIG. 4 is a flow diagram of a method of shutting down the engine system of FIG. 1, according to an example embodiment.

[0012] FIG. 5 is a flow diagram of a method of purging a fluid from the engine system of FIG. 1, according to an example embodiment.DETAILED DESCRIPTION10013] Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, computer-readable media, and systems for a fluid management system for a hydrogen fueled internal combustion engine system, for an aftertreatment system, and / or for a hydrogen fueled internal combustion engine and aftertreatment system. The fluid management system may purge or enable purging fluid from a hydrogen fueled internal combustion engine and / or an aftertreatment system. 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.[0014| During normal operation of an engine, rotation of the engine is caused by the combustion of fuel within a combustion cylinder. More specifically, combustion of fuel within a combustion cylinder causes rotation of a crankshaft (e.g., via actuating a piston and a connecting rod). The rotation of the crankshaft may cause the rotation of one or more camshafts (e.g., via one or more timing belts). As described above, rotation of one or more camshafts may cause one or more valves (e.g., an intake valve and / or an exhaust valve) to actuate between an open position and a closed position to allow air and / or an air and fuel mixture to enter the combustion cylinder and / or to allow an exhaust gas stream to exit the combustion cylinder. In some embodiments, rotation of the engine is caused by an electric machine, such as a motor or motor generator. The electric machine may be coupled to the crankshaft directly or indirectly (e.g., via a clutch, a drive shaft, and / or another component). In some embodiments, the electric machine may be an electric starter, such that rotation of the engine is caused by the electric starter. For example, the electric starter may “crank” or cause rotation of the crankshaft to facilitate starting the engine.10015 [ As described herein, an engine system may include an engine and an exhaust aftertreatment system in exhaust gas receiving communication with the engine. The exhaust aftertreatment system may include one or more components, such as a particulate filter configured to remove particulate matter 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 aftertreatment system, and one or more catalyst devices configured to facilitate conversion of the exhaust gas constituents (e.g., nitrogen oxides, NOx, sulfur oxides, SOx, etc.) to less harmful elements (e.g., water, nitrogen, N2, etc.), such as an oxidation catalyst, a selectively catalytic reduction (SCR) system, a three-way catalyst, and so on.10016] Advantageously, a control system or controller may control the operation of the engine system to selectively “purge” fluid from the engine system. As used herein, “purge” and similar terms are used to mean expel or remove, or substantially expel or remove (remove a majority of), undesirable contents (e.g., from the engine system). For example, fluids, such as water and hydrogen, may be purged from the engine system. The purged fluids may be replaced with another fluid, such as air.[0017| In some embodiments, 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. For example, the sensor data may include a “hydrogen content” at or proximate one or more components of the engine system. The “hydrogen content” is an amount (e.g., absolute amount, a relative amount, etc.) of hydrogen within a mixture. The amount may be expressed as a value, such as a mass value (e.g., measured in grams, kilograms, etc.), a weigh value (e.g., measured in ounces, pounds, etc.), or another suitable value, such as a molar value. In some embodiments, the amount may be expressed as a concentration (e.g., an amount of a substance divided by the total amount of a mixture), such as parts per million, percent weight, percent mass, molar concentration, volumetric concentration, and so on. For example, the hydrogen content in a gas stream may be a mass of the hydrogen, a concentration of hydrogen relative to the gas stream, a percentage of hydrogen by weight relative to the weight of the gas stream, etc. Similarly, a “water content” is an amount of water within a substance, such as a mixture. For example, the water content in a gas stream may be a mass of the water, a concentration of water relative to the gas stream, a percentage of water by weight relative to the gas stream, etc.

[0018] In some embodiments, the control system may compare sensor data to one or more thresholds to determine whether to implement an engine system purge. In other embodiments, the control system may implement an engine system purge based on receiving a particular input, such as an engine shutdown request.

[0019] As described herein, it may be desirable to purge undesirable contents from an engine system. Water (e.g., condensation) in an engine system (e.g., in a cylinder, or, more specifically, in a combustion chamber) can migrate into other components of the engine system, such as the crankcase oil, and can result in oxidation (rust) of one or more components and / or exposed surfaces. Similarly, water condensation in the exhaust system can promote oxidation of iron-based components or surfaces and may contaminate exhaust catalyst materials. Further, water condensation in the exhaust system can freeze in the presence of cold ambient temperatures which can lead to airflow restrictions (blockages) and / or damage to the catalysts. With respect to hydrogen fueled internal combustion engines,hydrogen (e.g., unbumed H2) in an engine system (e.g., in a cylinder, in an aftertreatment system, etc.) may become flammable due its high combustibility characteristic. Additionally, hydrogen in an engine system may promote “hydrogen embrittlement.” As described herein, hydrogen embrittlement refers to a phenomenon of hydrogen molecules diffusing into metal and reacting with carbon within the metal thereby changing the material properties of the components. For example, hydrogen embrittlement may cause the material of a component to become more brittle.

[0020] In an example embodiment, an engine system includes a hydrogen fueled internal combustion engine. The internal combustion engine includes one or more cylinders (e.g., combustion cylinders) for combusting hydrogen fuel and producing power. In some embodiments, the system includes one or more sensor configured to acquire data regarding a hydrogen content at or proximate one or more components of the engine system.

[0021] In an example operating implementation, a control system (e.g., a controller, a vehicle controller, etc.) receives an engine shutdown request (e.g., as a user input). The control system executes a shutdown procedure to purge excess fluid, such as water, in the engine system (e.g., in a cylinder and / or in an aftertreatment system). The shutdown procedure may include cutting off fuel supplied to the engine and preventing igniters (e.g., spark plugs) from igniting. The shutdown procedure may also include causing the engine to continue to rotate beyond normal shutdown rotations. In this way, the control system causes air to flow through the engine system thereby mitigating the collection of water condensation in the cylinders and / or aftertreatment system.

[0022] In another example operating implementation, a control system (e.g., a controller, a vehicle controller, etc.) utilizes one or more sensors (e.g., real sensors and / or virtual sensors) to acquire sensor data regarding a hydrogen content at or proximate one or more components of the engine system. The control system may compare the hydrogen content to one or more thresholds. The control system may execute an engine system purge responsive to determining that the hydrogen content exceeds one or more of the thresholds. The engine system purge may include causing the engine to rotate beyond normal shutdown rotations. In this way, the control system causes air to flow through the engine system thereby mitigatingthe collection of hydrogen in the cylinders and / or aftertreatment system. These and other features and benefits are described more fully herein below.

[0023] Referring now to FIG. 1, a schematic view of a block diagram of an engine system 100 is shown, according to an example embodiment. The engine system 100 includes an engine 102 and an aftertreatment system 120 in exhaust gas receiving communication with the engine 102. The system 100 includes a controller 140 (as shown in FIG. 3) and an operator input / output (I / O) device 130, where the controller 140 is communicably coupled to each of the aforementioned components.

[0024] In some embodiments, the engine system 100 includes a turbo device 122 disposed between the engine 102 and the aftertreatment system 120, such that the turbo device 122 is in exhaust gas receiving communication with the engine 102 and exhaust gas providing communication with the aftertreatment system 120. In these embodiments, the aftertreatment system 120 is in exhaust gas receiving communication with the engine 102 (e.g., via the turbo device 122).

[0025] In the configuration of FIG. 1, the engine 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, wheelloaders, fork-lift trucks, line-haul trucks, mid-range trucks (e.g., pick-up truck, etc.), sedans, coupes, tanks, airplanes, boats, and any other type of vehicle. In another embodiment, the engine 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.

[0026] In the configuration shown in FIG. 1, the engine 102 is a hydrogen internal combustion engine (ICE). The hydrogen ICE may consume hydrogen fuel to generate power. In some embodiments, the engine 102 may be part of a hybrid engine system having a combination of an internal combustion engine and at least one electric machine coupled to at least one battery. For example, as shown in FIG. 1, the engine system 100 may include an electric machine 128 (e.g., a motor, a motor generator, an electric starter, etc.) that is coupled to the engine 102 via a shaft (e.g., an output shaft, a drive shaft, a crankshaft, etc.). In someembodiments, the engine system 100 may be configured as a mild-hybrid powertrain, a parallel hybrid powertrain, a series hybrid powertrain, or a series-parallel powertrain.(0027] The engine 102 includes one or more cylinders 104 (e.g., combustion cylinders). The cylinders 104 are disposed within a combustion chamber of the engine 102. As shown in FIG. 2, each cylinder 104 has a corresponding igniter 106 (e.g., spark plug, glow plug, etc.). The igniter 106 is configured to ignite fuel (e.g., hydrogen) within a corresponding cylinder 104. In some embodiments, and as shown in FIG. 2, each cylinder 104 has a corresponding fuel injector 108. In these embodiments, the fuel injectors 108 are configured to provide fuel (e.g., hydrogen) to a corresponding cylinder 104. In other embodiments, the fuel injector(s) 108 may be positioned upstream of the cylinders 104 (e.g., at or within an intake manifold, such as the intake manifold 112, described herein). In these embodiments, the fuel injector(s) 108 are configured to provide fuel (e.g., hydrogen) upstream of the cylinders 104 such that the cylinders 104 receive fuel from the fuel injector(s) 108.(0028] In some embodiments, each cylinder 104 includes an intake valve 160 and an exhaust valve 162. The intake valve 160 is selectively positionable between an open position and a closed position. In the closed position, the intake valve 160 substantially prevents a gas stream from flowing into or out of the cylinder 104. In the open position and positions between the open position and the closed position, the intake valve 160 allows a gas stream (e.g., an intake gas stream, such as air) to enter the cylinder 104. In some embodiments, the intake valve 160 allows the intake gas stream to flow into the cylinder 104 from the intake manifold 112. The exhaust valve 162 is selectively positionable between an open position and a closed position. In the closed position, the exhaust valve 162 substantially prevents a gas stream from flowing into or out of the cylinder 104. In the open position and in positions between the open position and the closed position, the exhaust valve 162 allows a gas stream (e.g., an exhaust gas stream) to exit the cylinder 104. In some embodiments, the exhaust valve 162 allows the exhaust gas stream to flow into the exhaust manifold 116, described herein.(0(129] The intake valve 160 and the exhaust valve 162 are each operable between an open position and a closed position. When the engine 102 is rotated, the intake valve 160 and the exhaust valve 162 are each operated between the open position and the closed position. Asthe intake valve and the exhaust valve 162 are actuated, an intake gas stream (e.g., air or an air-fuel mixture) flows into the cylinder 104 and an exhaust gas stream (e.g., exhaust gas including air, hydrogen, and / or byproducts from combusting the air-fuel mixture, such as NOx, SOx, water, etc.) flows out of the cylinder 104. In this way, rotation of the engine 102 may facilitate the movement of a gas stream from the intake manifold 112 to the exhaust manifold 116.

[0030] In some embodiments, the engine 102 may be rotated by an outside force, such as an electric machine. In these embodiments, fuel is not provided to the cylinder 104 and the igniter 106 does not ignite. Further, the intake valve 160 and the exhaust valve 162 are each actuated thereby causing a gas stream (e.g., air) to pass through the engine 102.

[0031] Referring still to FIG. 1, the engine 102 includes six cylinders 104. However, it should be understood that the engine 102 may include more or fewer cylinders 104 (e.g., at least one) than as shown in FIG. 1. Furthermore, the cylinders 104 may be provided in varying arrangements (e.g., in-line, horizontal, V, or other suitable cylinder arrangement).

[0032] The engine system 100 includes an intake conduit 110 and an intake manifold 112. The intake conduit 110 is configured to route an intake gas stream, including air (e.g., ambient air, compressed air, etc.), to the intake manifold 112. The intake manifold 112 is configured to route the intake gas stream from an intake conduit 110 into the engine 102. More specifically, the intake manifold 112 is configured to route air from the intake conduit 110 to each of the cylinders 104.

[0033] The engine system 100 includes an intake air throttle (IAT) valve 114. The IAT valve 114 is disposed at the intake conduit 110 and upstream of the intake manifold 112. The IAT valve 114 is structured to control an amount of air supplied to the engine 102. The IAT valve 114 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 114 allows a maximum amount of air to flow from the air intake to the engine 102. In the closed position, the IAT valve 114 allows a minimum amount of air to flow from the air intake to the engine 102. The controller 140 may selectively actuate the IAT valve 114 (e.g., by controlling the actuator) ina plurality of positions between and / or including the open position and the closed position to adjust the amount of air received by the engine 102.(0034] In some embodiments, the engine system 100 includes an air supply 115 (e.g., a forced air supply). The air supply 115 is disposed at the intake conduit 110 and upstream of the IAT valve 114. The air supply 115 is structured to provide an air stream to the engine 102. The air supply 115 may be controlled by the controller 140, such that the controller 140 is operative to adjust an amount of air provided by the air supply 115. In some embodiments, the air supply 115 is or includes a compressed air supply (e.g., a compressed air storage tank). In other embodiments, the air supply 115 is a supercharger or other device configured to provide compressed air to the engine 102. In some embodiments, the air supply 115 is belt driven, chain driven, gear driven, or electric driven. In some embodiments, the air supply 115 is or is part of the turbo device 122, such as a turbocharger, as described herein below. In other embodiments, the engine system 100 does not include the air supply 115.(0035] The engine system 100 includes an exhaust manifold 116 and an exhaust conduit 118. The exhaust manifold 116 is configured to route an exhaust gas stream from the engine to the exhaust conduit 118. More specifically, the exhaust manifold 116 is configured to route an exhaust gas stream from each of the cylinders 104 to the exhaust conduit 118. The exhaust conduit 118 is configured to route the exhaust gas stream from the exhaust manifold 116 to a downstream component, such as the aftertreatment system 120 and / or the turbo device 122. In some embodiments, a first portion of the exhaust conduit 118 is disposed between the exhaust manifold 116 and turbo device 122. The first portion of the exhaust conduit 118 is configured to route the exhaust gas stream from the exhaust manifold 116 to turbo device 122. In some embodiments, a second portion of the exhaust conduit 118 is disposed between the aftertreatment system 120 and the turbo device 122. The second portion of the exhaust conduit 118 is configured to route the exhaust gas stream from the turbo device 122 to the aftertreatment system 120.

[0036] The aftertreatment system 120 is in exhaust gas receiving communication with the engine 102. The aftertreatment system 120 includes components used to reduce exhaust emissions, such as a selective catalytic reduction (SCR) catalyst, an oxidation catalyst (DOC), a particulate filter (PF), an exhaust fluid doser with a supply of exhaust fluid, aplurality of sensors for monitoring the aftertreatment system (e.g., a nitrogen oxide (NOx) sensor, temperature sensors, etc.), and / or still other components.(0037] The turbo device 122 may be any type of turbo machinery, such as a turbocharger, a variable geometry turbocharger, a power turbine, etc. The turbo device 122 may be operatively coupled to the engine 102 and / or another component of the engine system 100, such as a drivetrain, a battery, an electric machine, or other suitable component. In some embodiments, the turbo device 122 is configured to compress a gas stream (e.g., an intake gas stream, an exhaust gas stream, etc.) and provide the compressed gas stream to the engine 102. For example, as shown in FIG. 1, the turbo device 122 may be coupled to the intake manifold 112 such that the turbo device is operative to provide the compressed gas stream to the engine 102 (e.g., via the intake manifold 112).

[0038] The engine system 100 also includes a fuel system 124. The fuel system 124 is configured to provide fuel (e.g., hydrogen) to the engine 102. More specifically, the fuel system 124 is configured to provide fuel to each of the one or more cylinders 104 (e.g., via the fuel injectors 108). The fuel system 124 may include one or more components for providing the fuel to the engine 102, such as a storage tank for storing the fuel, and / or one or more regulators (e.g., valves, solenoids, etc.) for controlling an amount or a timing of fuel provided to the engine 102.

[0039] In some embodiments, the controller 140 is operatively coupled to the fuel system 124 and / or the fuel injectors 108, such that the controller 140 may control the operation of the fuel system 124 and / or the fuel injectors 108. More specifically, the controller 140 may control the fuel system 124 and / or the fuel injectors 108 to control an amount and / or a timing of fuel provided to the engine 102.

[0040] As shown, a plurality of sensors 125 are included in the engine system 100. The number, placement, and type of sensors included in the engine system 100 is 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., NOx sensors, oxygen sensors, FkO / humidity sensors, hydrogen sensors, etc.), temperature sensors, particulate matter (PM) sensors, flow rate sensors (e.g., mass flow rate sensors, volumetricflow rate sensors, etc.), other exhaust gas emissions constituent sensors, pressure sensors, some combination thereof, and so on. The gas constituent sensors may include a hydrogen sensor that is structured to acquire data indicative of the presence of hydrogen at or proximate the sensor 125, such as in a gas stream (e.g., a hydrogen content of the gas stream). The data from the hydrogen sensor may be used to determine whether to execute an engine system purge procedure.

[0041] As shown in FIG. 1, the sensors 125 may be located at or proximate the intake conduit 110, the intake manifold 112, the exhaust manifold 116, the exhaust conduit 118, and / or the aftertreatment system 120. For example, the engine system 100 may include sensors 125 located both before and after the aftertreatment system 120. It should be understood that the location of the sensors may vary, and the engine system 100 may include more or fewer sensors than as shown in FIG. 1.

[0042] 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.). The sensors may further include sensors associated with other components of the vehicle, such as the aftertreatment system 120, the turbo device 122, or the fuel system 124. For example, the sensor may include speed sensor of the turbo device 122, a fuel quantity and injection rate sensor, fuel rail pressure sensor, etc.).

[0043] 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 102 (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 102. 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. As utilized herein, the term “estimating” and like terms are used to refer to determining an approximate current or past value based on data (e.g., sensor data, historical sensor data, real-time sensor data, etc.), which may be close but not necessarilyexactly the actual value of the determined current or past parameter value. In some embodiments, estimating the current or past value can be performed using one or more models (e.g., statistical models, artificial intelligence models, machine learning models, etc.). For example, estimating a hydrogen content can include using data, such as sensor data, with a model to determine the hydrogen content. As utilized herein, the term “measuring” and like terms are used to refer to determining an approximate current or past parameter value based on detecting or receiving information regarding the parameter (e.g., using a sensor). The measured value may be close but not necessarily exactly the actual value of the measured current or past parameter value. As utilized herein, the term “determining” and like terms, in addition to the plain meaning of the word, are used to refer to estimating or measuring a parameter value. 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), estimated (e.g., by one or more virtual sensors or by a computer device or processing circuit), and / or determined based on a target value.

[0044] The controller 140 is coupled, and particularly communicably coupled, to the sensors 125. Accordingly, the controller 140 is structured to receive data from one more of the sensors 125 and provide instruct! ons / informati on to the one or more sensors 125. The received data may be used by the controller 140 to control one more components in the system 100 as described herein.

[0045] As briefly described above, the engine system 100 includes a shaft 126 (e.g., an output shaft, a drive shaft, a crankshaft, etc.). The shaft 126 is configured to transmit power output by the engine 102 to another component, such as an axle, a wheel, or another shaft. In some embodiments an intermediate component couples the engine 102 to the shaft 126, such as a clutch, a transmission, etc.

[0046] In some embodiments, the engine system 100 includes an electric machine 128. The electric machine 128 is configured to use electrical power (e.g., from a battery or an alternator) to output mechanical power. For example, the electric machine 128 is coupled to the shaft 126 such that the shaft 126 is operable to receive power output by the electricmachine 128. In some embodiments, the electric machine 128 is coupled to the engine 102 (e.g., via the shaft 126) such that the electric machine 128 is operable to rotate the engine 102.

[0047] In some embodiments, the engine system 100 includes a compressed air system, which may be or include an air starter system 132. In some embodiments, the compressed air system is coupled to the engine 102. In other embodiments, the compressed air system is coupled to the air starter system 132. In an example embodiment, the air starter system 132 is coupled to the engine 102. In another example embodiment, the air starter system 132 is directly coupled to the shaft 126 and coupled to the engine via the shaft 126. In other embodiments, the air starter system 132 is coupled to the shaft 126 via an intermediate component, such as a flywheel (not shown). The air starter system 132 is configured to use compressed air to output mechanical power. More specifically, the air starter system 132 may use compressed air to facilitate “rotating” the engine 102. As described herein, “rotating” an engine refers to actuating one or more components of an engine system. For example, when an engine is rotated, a crankshaft, one or more camshafts one or more timing belts, and other components may be rotated to facilitate operation of the engine. Further, when an engine is rotated, a piston and a connecting rod may actuate relative to a combustion chamber. Rotation of the one or more camshafts may cause one or more valves (e.g., an intake valve and / or an exhaust valve) to actuate between an open position and a closed position. Rotation of the engine may be measured in rotations per minute (RPM). More specifically, rotation of the engine may be measured by an RPM of the crankshaft.

[0048] The air starter system 132 is coupled to the shaft 126 (e.g., directly or via the flywheel) such that the air starter system 132 is operable to provide mechanical power to rotate the shaft 126. In this way, the air starter system 132 is operable to rotate the engine 102 by rotating the shaft 126. In an example scenario, the air starter system 132 uses compressed air to generate a torque to rotate the shaft 126. As the shaft 126 starts to rotate, the shaft 126 causes the engine 102 to rotate. Thus, the compressed air system may use compressed air to rotate the engine 102. When rotating the engine 102 without powering the engine 102, the fuel system 124 does not provide fuel to the engine 102. When rotating the engine 102 to start the engine 102, the fuel system 124 may provide fuel to the engine 102, and the air startersystem 132 may cease rotating the shaft 126. In some embodiments, the compressed air system may cause the engine 102 to rotate for a predetermined number of rotations or a predetermined time period. In some embodiments, when rotating the engine 102 to start the engine 102, the compressed air system may cause the engine 102 to rotate for a predetermined number of combustion events or until a speed of the engine exceeds a predetermined threshold. In some embodiments, the controller 140 is configured to cause the fuel system 124 to provide the hydrogen fuel to the engine 102 after the compressed air system has started rotating the engine 102 (e.g., such that combustion occurs within the engine 102).

[0049] The operator input / output (I / O) 130 device may be coupled to the controller 140, such that information may be exchanged between the controller 140 and the I / O device, 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 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 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 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.

[0050] The controller 140 is structured to control, at least partly, the operation of the system 100 and associated sub-systems, such as the engine 102 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, thecontroller 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. 3.

[0051] 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 unit, an engine control module, etc.

[0052] Now referring to FIG. 3, 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 water purge circuit 212, a hydrogen purge circuit 214, and a communications interface 216. The controller 140 is structured to facilitate purging fluid from the engine 102 and / or the aftertreatment system 120. In some embodiments, the fluid is water that entered the system 100 from the ambient air or that was produced by combusting hydrogen in the presence of air (or, more specifically, oxygen). In some embodiments, the fluid is hydrogen gas. The hydrogen may enter the engine 102 from the fuel system 124. The hydrogen may enter the aftertreatment system 120 as exhaust from the engine 102 (e.g., when the hydrogen is not combusted by the engine 102. Specific processes for purging fluid from the engine 102 and / or the aftertreatment system 120 are described herein below.10053] In one configuration, the water purge circuit 212 and / or the hydrogen purge circuit 214 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" programminglanguage 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.).

[0054] In another configuration, the water purge circuit 212 and / or the hydrogen purge circuit 214 is embodied as a hardware unit, such as one or more electronic control units. As such, the water purge circuit 212 and / or the hydrogen purge circuit 214 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 water purge circuit 212 and / or the hydrogen purge circuit 214 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, the water purge circuit 212 and / or the hydrogen purge circuit 214 may include any type of component for accomplishing or facilitating 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 water purge circuit 212 and / or the hydrogen purge circuit 214 may also include or be programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like. The water purge circuit 212 and / or the hydrogen purge circuit 214 may include one or more memory devices for storing instructions that are executable by the processor(s) of the water purge circuit 212 and / or the hydrogen purge circuit 214. 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 water purge circuit 212 and / or the hydrogen purge circuit 214 may be geographically dispersed throughout separate locations in the vehicle. Alternatively, and as shown, the water purge circuit 212 and / or the hydrogen purge circuit 214 may be embodied in or within a single unit / housing, which is shown as the controller 140.

[0055] In the example shown, the controller 140 includes the at least one processing circuit 202 having the at least one processor 204 and the at least one memory device 206. Theprocessing circuit 202 may be structured or configured to execute or implement the instructions, commands, and / or control processes described herein with respect to the water purge circuit 212 and / or the hydrogen purge circuit 214. The depicted configuration represents the water purge circuit 212 and / or the hydrogen purge circuit 214 as being embodied as machine or computer-readable media storing instructions (which may be stored by the memory device 206). However, as mentioned above, this illustration is not meant to be limiting as the present disclosure contemplates other embodiments where the water purge circuit 212 and / or the hydrogen purge circuit 214, is configured as a hardware unit. All such combinations and variations are intended to fall within the scope of the present disclosure.

[0056] 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 water purge circuit 212 and / or the hydrogen purge circuit 214 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 multithreaded instruction execution. All such variations are intended to fall within the scope of the present disclosure.

[0057] 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 includedynamic 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.

[0058] 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).

[0059] As shown in FIG. 3, the communications interface 216 may enable communication with the engine 102, the aftertreatment system 120 (and / or a component thereof), the one or more sensors 125, the IAT valve 114, and / or the fuel system 124. In some embodiments, the communications interface 216 may enable communication with the air supply 115. In some embodiments, the communications interface 216 may enable communication with the electric machine 128.

[0060] In an example embodiment, the controller 140 is structured to enable starting the engine system 100. In some embodiments, the controller 140 is structured to receive an engine start request. The engine start request may include one or more of a key on, an engine start button press, or another suitable engine start request. Responsive to receiving the engine start request, the controller 140 may cause the engine 102 to start by enabling an electric starter, such as the electric machine 128, enabling the fuel system 124 to deliver fuel to thecylinders 104, enabling the IAT valve 114 to provide air to the cylinders 104, and / or enabling the igniters 106 to ignite an air / fuel mixture within the cylinders 104.(0061] The controller 140 is structured to enable operation of the engine 102. For example, during operation, the controller 140 may receive one or more user inputs (e.g., via the operator I / O device 130) such as a user pressing an accelerator, a user pressing a brake, or other suitable user input. In operation, the controller 140 may control (e.g., increase, decrease, or maintain) an amount of air provided to the engine 102 by selectively controlling the IAT valve 114. The controller 140 may control (e.g., increase, decrease, or maintain) an amount of fuel provided to the engine 102 by selectively operating the fuel system 124 and / or the fuel injectors 108. The controller 140 may control the combustion of the air / fuel mixture in the cylinders 104 by controlling the operation of the igniters 106.

[0062] In some embodiments, the controller 140 is configured to receive an engine shutdown request (e.g., from a user such as via the operator I / O device 130). The shutdown request may include one or more of a key off, an engine stop button press, or another suitable shutdown request. In some embodiments, the controller 140 itself provides the shutdown request (e.g., when the controller 140 is provided in an autonomous driving vehicle). In some embodiments, the shutdown request is received from a computing system other than the controller (e.g., a remote computing system, an edge computing device, etc. Responsive to receiving the engine shutdown request, the controller 140 may enable a shutdown procedure. During a “normal” shutdown procedure, shutting down the engine may include stopping combustion in the cylinders 104. Stopping combustion may include disabling the fuel system 124 such that fuel is not delivered to the cylinders 104, closing the IAT valve 114 such that air does not flow into the intake manifold 112 (nor the cylinders 104), and / or disabling the igniters 106 such that an air / fuel mixture within the cylinders 104 is not ignited. During the normal shutdown procedure, the engine 102 may continue to rotate for a brief period of time. For example, before enabling the shutdown procedure the engine 102 may be rotating at a certain speed (e.g., engine speed, rotational speed, etc.) and may continue to rotate after combustion has stopped due to inertia until friction brings the engine 102 to rest. Thus, after enabling the shutdown procedure the engine 102 may rotate a number of rotations referred to herein as “normal shutdown rotations.” The engine 102 may rotate for a certain period oftime referred to herein as a “normal shutdown rotation period.” The quantity of normal shutdown rotations and / or the time period of the normal shutdown rotation period may be a function of engine speed when the shutdown procedure is enabled. In some embodiments, the controller 140 may determine a normal amount of rotations at shutdown in various circumstances based on receiving information from an engine RPM sensor measuring the rotations when the engine 102 is shut down, such as after short operational periods (e.g., less than 30 minutes or 5 miles), long operational periods (more than 5 miles and more than 30 minutes), extended periods (more than 4 hours), during various climates (e.g., temperatures below a first predetermined threshold, temperatures above a second predetermined threshold, etc.), and so on. These conditions may change the "normal" amount of rotations. Accordingly, the controller 140 may determine a metric for each condition, the metric being an average, median, etc. number of rotations for each situation. The controller 140 may extend the number of rotations relative to this metric. In some embodiments, these metrics are determined by the controller 140 (e.g., on-board the vehicle) such that the controller 140 may update the metrics over time. In other embodiments, the metrics may be determined in a test center and the metrics are provided to the controller 140.

[0063] The water purge circuit 212 is structured to enable or a cause a purging of fluid, such as water, from the engine 102 and / or the aftertreatment system 120. In some embodiments, the responsive to the controller 140 receiving an engine shutdown request, the water purge circuit 212 may execute a water purge shutdown procedure that is different than the “normal” shutdown procedure described above. In some embodiments, when the water purge circuit 212 executes the water purge shutdown procedure, the water purge circuit 212 causes the engine 102 to continue to rotate beyond normal shutdown rotations. In particular, the number of rotations may be a preset amount, a preset time of rotations, and / or another attribute that defines the number of rotations to exceed the normal shutdown rotations. In some embodiments, the water purge circuit 212 causes the engine 102 to continue to rotate for a certain period of time (e.g., 30 seconds, 1 minute, 10 minutes, etc.) and / or for a certain number of rotations (e.g., 100 rotations, 1000 rotations, etc.).

[0064] In some embodiments, the water purge circuit 212 is structured to enable a modified shutdown procedure to purge water from the engine 102 and / or the aftertreatment system120. In the modified shutdown procedure, the engine continues to rotate beyond normal shutdown rotations by way of one or more of (i) an increased engine inertia, (ii) the electric machine 128 including a battery powered starter and / or a battery powered motor generator, and / or (iii) the air starter system 132.

[0065] In some embodiments, the water purge circuit 212 enables a shutdown procedure that increases an “inertia” of the engine 102 before stopping combustion (e.g., disabling the igniters 106, the fuel injectors 108, the IAT valve 114, and / or the fuel system 124). As used herein, “inertia” and similar terms are used to mean an amount of energy (e.g., kinetic energy) stored by a component (e.g., in a rotating component). For example, a kinetic energy of a rotating component may be expressed by Equation 1 below, where “K” is the kinetic energy, “I” is the moment of inertia of the component, and “co” is the rotational speed (e.g., in rotations per minute, rotations per second, radians per second, etc.).

[0066] K = ± (1)

[0067] The moment of inertia “I” of the engine 102 may be a known and substantially constant quantity. Thus, increasing the inertia of the engine 102 may include increasing a speed of the engine. The water purge circuit 212 is configured to increase a speed of the engine by, for example, allowing a greater amount of an air / fuel mixture to enter the cylinders 104 by causing the fuel system 124 to increase an amount of fuel provided to the engine 102, causing the IAT valve 114 to allow more air into the engine 102, and / or operating each of the intake valves 160 to allow a greater amount of the air / fuel mixture into the cylinders 104. In this way, the water purge circuit 212 increases the inertia of the engine 102 (e.g., by increasing the speed of the engine) such that the engine 102 continues to rotate for at least a predetermined time period and / or at least a predetermined number of rotations after stopping combustion (e.g., ceasing providing fuel by the fuel system 124).

[0068] In some embodiments, the water purge circuit 212 may increase the engine speed to a predetermined value (e.g., a target engine speed). In some embodiments, the predetermined value corresponds to a predetermined number of rotations and / or a predetermined time period of rotating after stopping combustion. For example, the water purge circuit 212 may increase the engine speed to a first value that causes the engine to continue to rotate for 15 secondsafter stopping combustion. In another example, the water purge circuit 212 may increase the engine speed to a second value, different than the first value, that causes the engine to continue to rotate for 30 seconds after stopping combustion.

[0069] In some embodiments, the water purge circuit 212 causes a battery powered starter to rotate the engine 102. In these embodiments, the electric machine 128 is an engine starter that is coupled to a power source, such as a battery (not shown), and the electric machine 128 is coupled to the engine 102 via the shaft 126 (e.g., a crankshaft). The water purge circuit 212 is configured to cause the battery powered starter to rotate the engine at a predetermined engine speed (e.g., between 200 RPM and 600 RPM). In some embodiments, the water purge circuit 212 is configured to cause the battery powered starter to rotate the engine 102 after stopping combustion (e.g., ceasing providing fuel by the fuel system 124). In other embodiments, the water purge circuit 212 is configured to cause the battery powered starter to rotate the engine 102 prior to stopping combustion. In some embodiments, the water purge circuit 212 is configured to cause the battery powered starter to rotate the engine 102 before the engine 102 stops rotating (e.g., while the engine speed is at or above a predetermined threshold, such as zero). In other embodiments, the water purge circuit 212 is configured to cause the battery powered starter to rotate the engine 102 after the engine 102 stops rotating (e.g., after the engine speed is at or below a predetermined threshold, such as zero).

[0070] In some embodiments, the water purge circuit 212 is configured to sync or substantially sync (i.e., so they rotate at the same or substantially the same speed) the rotational speed of the engine with the rotational speed of the battery powered starter. In these embodiments, the water purge circuit 212 may receive data indicative of the engine speed (e.g., from one or more sensors 125). For example, the water purge circuit 212 may cause the battery powered starter to rotate the engine at a first predetermined engine speed responsive to determining and / or receiving an indication that the engine 102 is rotating at a second speed. In some embodiments, the first speed may be equal to the second speed. In other embodiments, the second speed may be less than or equal to the first speed. That is, the water purge circuit 212 may cause the battery powered starter to rotate the engine 102 at the first predetermined engine speed responsive to the second speed (e.g., the speed of the engine 102) being at or below the first engine speed.[00711 In some embodiments, the water purge circuit 212 causes a battery powered starter to rotate the engine 102 for a predetermined number of rotations and / or for a predetermined amount of time.

[0072] In some embodiments, the water purge circuit 212 causes a motor or a motor generator to rotate the engine 102. In these embodiments, the electric machine 128 is a motor or a motor generator that is coupled to a power source, such as a battery (not shown), and the electric machine 128 is coupled to the engine 102 via the shaft 126 (e.g., a drive shaft, an output shaft, etc.). In some embodiments, the shaft 126 is coupled to the engine 102 via one or more intermediate components, such as a clutch. The water purge circuit 212 is configured to cause the motor generator to rotate the engine at a predetermined engine speed. In some embodiments, the water purge circuit 212 is configured to cause the motor generator to rotate the engine 102 after stopping combustion (e.g., ceasing providing fuel by the fuel system 124). In other embodiments, the water purge circuit 212 is configured to cause the motor generator to rotate the engine 102 before stopping combustion. In some embodiments, the water purge circuit 212 is configured to cause the motor generator to rotate the engine 102 before the engine 102 stops rotating (e.g., while the engine speed is at or above a predetermined threshold, such as zero). In other embodiments, the water purge circuit 212 is configured to cause the motor generator to rotate the engine 102 after the engine 102 stops rotating (e.g., after the engine speed is at or below a predetermined threshold, such as zero).100731 In some embodiments, the water purge circuit 212 causes the motor generator to rotate the engine 102 for a predetermined number of rotations and / or for a predetermined amount of time.

[0074] In some embodiments, the water purge circuit 212 causes the air starter system 132 to rotate the engine 102. The water purge circuit 212 is configured to cause the air starter system 132 to rotate the engine at a predetermined engine speed (e.g., between approximately 200 RPM and 600 RPM). In some embodiments, the water purge circuit 212 is configured to cause the air starter system 132 to rotate the engine 102 after stopping combustion (e.g., ceasing providing fuel by the fuel system 124). In other embodiments, the water purge circuit 212 is configured to cause the battery powered starter to rotate the engine 102 prior to stopping combustion. In some embodiments, the water purge circuit 212 is configured tocause the air starter system 132 to rotate the engine 102 before the engine 102 stops rotating (e.g., while the engine speed is at or above a predetermined threshold, such as zero). In some embodiments, the water purge circuit 212 is configured to cause the air starter system 132 to rotate the engine 102 after the engine 102 stops rotating (e.g., after the engine speed is at or below a predetermined threshold, such as zero).

[0075] In some embodiments, the water purge circuit 212 cause the IAT valve 114 to at least partially open during the shutdown procedure such that air flows through the intake conduit 110 (e.g., past the at least partially open IAT valve 114) and into the engine 102 (e.g., via the intake manifold 112).

[0076] In any of the above-described embodiments, rotating the engine 102 causes one or more valves (e.g., the intake valve 160 and / or the exhaust valve 162) to actuate such that air (e.g., ambient air) is passed through the engine 102. As air passes through the engine 102, water is “purged” (e.g., displaced or moved) by the air and flows downstream (e.g., into the exhaust manifold, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120). In some embodiments, as air passes through the engine and / or through one or more of the downstream components (e.g., the exhaust manifold, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120) the air also purges water within one or more of the downstream components. For example, as the engine 102 is rotated, air passing through the engine is routed to the aftertreatment system 120 (e.g., via the exhaust manifold and / or the exhaust conduit 118) such that the air purges the water within the aftertreatment system 120.

[0077] In some embodiments, the water purge circuit 212 is configured to enable or cause an air supply 115 during the shutdown procedure. In these embodiments, the air supply 115 is configured to provide air to flow through the engine 102. In this way, the air provided by the air supply 115 facilitates purging water from the engine 102 and / or a downstream component, such as one or more of the exhaust manifold 116, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120. The purged water may flow out of the aftertreatment system 120 and to the atmosphere.

[0078] In some embodiments, the water purge circuit 212 is configured to provide a notification that the engine shutdown procedure has completed after the engine 102 has rotated the predetermined number of rotations and / or the predetermined amount of time has elapsed. In some embodiments, the water purge circuit 212 is configured to provide the notification responsive to receiving data indicative of the engine speed being zero (e.g., from one or more sensors). In some embodiments, the water purge circuit 212 may provide the notification via the input / output device 130. In other embodiments, the water purge circuit 212 does not provide a notification.

[0079] The hydrogen purge circuit 214 is structured to enable purging hydrogen from the engine 102 and / or the aftertreatment system 120. In some embodiments, the controller 140 and / or the hydrogen purge circuit 214 may receive information indicative of a hydrogen content in or proximate the engine 102 and / or in or proximate the aftertreatment system 120. The hydrogen purge circuit 214 may compare the hydrogen content to a predefined threshold value (e.g., a maximum hydrogen content value). Responsive to determining that the hydrogen content exceeds (e.g., does not satisfy) the threshold value, the hydrogen purge circuit 214 may enable or cause a hydrogen purge procedure. Responsive to determining that the hydrogen content does not exceed (e.g., satisfies) the threshold value, the hydrogen purge circuit 214 does not enable the hydrogen purge procedure.

[0080] In some embodiments, the hydrogen purge circuit 214 is structured to enable purging hydrogen from the engine 102 and / or the aftertreatment system 120 responsive to determining that an engine shutdown procedure has completed. For example, the hydrogen purge circuit 214 may enable purging hydrogen from the engine 102 and / or the aftertreatment system 120 responsive to receiving information indicative of the engine speed being zero.

[0081] In some embodiments, before executing a hydrogen purge procedure, the hydrogen purge circuit 214 is structured to compare a hydrogen content value to a threshold value. As described herein a “hydrogen content” value refers to an amount or concentration of hydrogen in or at a component of the system 100. For example, a hydrogen content value of the engine 102 may be an amount or concentration of hydrogen in or at the engine 102. In another example, the hydrogen content of an exhaust gas stream may be an amount or concentration of hydrogen in an exhaust gas stream that flows from the engine 102, to theaftertreatment system 120, and / or through components therebetween (e.g., the exhaust manifold 116, the exhaust conduit 118, and / or the turbo device 122). In this example, the hydrogen content value may be measured at or proximate any of the above-described components.10082] The hydrogen content value may be based on a measured value (e.g., a value measured by one or more sensors 125) and / or an estimated value (e.g., a value determined based on another measured value). In some embodiments, the hydrogen content may be measured directly (e.g., by one or more sensors 125 configured as a hydrogen sensor). In some embodiments, the hydrogen content value is based on a measured value of a different exhaust gas constituent, such as oxygen (O2), nitrogen oxides (NOx), carbon oxides (CO, CO2), etc. that is measured by one or more sensors, such as an oxygen sensor, etc. In these embodiments, the controller 140 may estimate or determine the hydrogen content based on the content of another exhaust gas constituent. For example, the controller 140 may use one or more of a model (e.g., a mathematical model, a machine learning model, an artificial intelligence model, etc.) or a lookup table that correlates an exhaust gas constituent content to a hydrogen content to estimate and / or determine the hydrogen content value. For example, a model and / or a lookup table may correlate at least one of oxygen content, nitrogen oxide content, or another exhaust gas constituent content to a hydrogen content. In another example embodiment, the controller 140 may estimate or determine the hydrogen content by way of “cross-sensitivity” of the non-hydrogen exhaust gas constituent sensors. For example, the controller 140 may use one or more of a model (e.g., a mathematical model, a machine learning model, an artificial intelligence model, etc.) or a lookup table that correlates crosssensitivity sensor data with a hydrogen content value.

[0083] In some embodiments, the hydrogen content value may be estimated based on detecting (e.g., by one or more sensors 125) a leak in the fuel system 124. For example, the controller 140 may receive information indicative of a leak in the fuel system 124 from one or more sensors 125. For example, the information indicative of a leak in the fuel system 124 may include a change (e.g., decrease) in pressure of a hydrogen storage tank (e.g., measured by a pressure sensor). In other embodiments, the information indicative of a leak in the fuel system 124 may include data from one or more hydrogen detection sensors. The one or morehydrogen detection sensors may be configured to acquire data regarding the presence of hydrogen at or proximate the hydrogen detection sensors. In some embodiments, the data regarding the presence of hydrogen at or proximate the hydrogen detection sensors may include a hydrogen content value. In other embodiments, the data regarding the presence of hydrogen at or proximate the hydrogen detection sensors include a binary indication (e.g., yes or no) of whether hydrogen is present and / or whether a hydrogen content is at or above a predetermined threshold. In some embodiments, the hydrogen detection sensors may be positioned at or proximate the fuel system 124. In other embodiments, the hydrogen detection sensors may be positioned at another location in the system 100.

[0084] As briefly described above, the hydrogen content value may correspond to a location within the engine 102 or downstream of the engine 102, such as the exhaust manifold 116, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120. In an example embodiment, the hydrogen content value corresponds to a location within the aftertreatment system 120, such as an inlet of the aftertreatment system 120.

[0085] Responsive to receiving and / or determining the hydrogen content value, the hydrogen purge circuit 214 may compare the hydrogen content value to a threshold value. Responsive to determining that the hydrogen content value exceeds the threshold value (e.g., the hydrogen content value does not satisfy the threshold value), the hydrogen purge circuit 214 may execute a hydrogen purge procedure. Responsive to determining that the hydrogen content value is less than or equal to the threshold value (e.g., the hydrogen content value satisfies the threshold value), the hydrogen purge circuit 214 does not execute the hydrogen purge procedure.

[0086] In some embodiments, hydrogen purge circuit 214 is configured to enable or execute the hydrogen purge procedure (e.g., responsive to determining that the hydrogen content value exceeds the threshold value). In some embodiments, when the hydrogen purge circuit 214 executes the hydrogen purge procedure, the hydrogen purge circuit 214 causes the engine 102 to rotate. As briefly described above, the hydrogen purge circuit 214 may cause the engine 102 to continue to rotate after an engine shutdown procedure is completed (e.g., after the engine 102 has stopped rotating). In some embodiments, the hydrogen purge circuit 214causes the engine 102 to rotate by way of the electric machine 128 including a battery powered starter and / or a battery powered motor generator and / or the air starter system 132.(0087] In some embodiments, the hydrogen purge circuit 214 causes a battery powered starter to rotate the engine 102. In these embodiments, the electric machine 128 is an engine starter that is coupled to a power source, such as a battery (not shown), and the electric machine 128 is coupled to the engine 102 via the shaft 126 (e.g., a crankshaft). The hydrogen purge circuit 214 is configured to cause the battery powered starter to rotate the engine at a predetermined engine speed (e.g., between approximately 200 RPM and 600 RPM). In some embodiments, the hydrogen purge circuit 214 is configured to cause the battery powered starter to rotate the engine 102 after stopping combustion (e.g., ceasing providing fuel by the fuel system 124). In some embodiments, the hydrogen purge circuit 214 is configured to cause the battery powered starter to continue to rotate the engine 102 after the engine 102 stops rotating (e.g., after the engine speed is at or below a predetermined threshold, such as zero). For example, the controller may receive an indication that the engine 102 has stopped rotating and then cause rotation of the engine 102 after an initial stoppage of rotation. In this way, the stoppage of rotation may be the trigger condition for the controller to continue to cause rotation of the engine. In other embodiments, the hydrogen purge circuit 214 is configured to cause the battery powered starter to rotate the engine 102 before the engine 102 stops rotating (e.g., while the engine speed is at or above a predetermined threshold, such as zero).

[0088] In some embodiments, the hydrogen purge circuit 214 is configured to cause the battery powered starter to rotate the engine 102 responsive to the hydrogen content value being at or above to the threshold value.(0089] In some embodiments, the hydrogen purge circuit 214 causes a battery powered starter to rotate the engine 102 for a predetermined number of rotations and / or for a predetermined amount of time.100901 In some embodiments, the hydrogen purge circuit 214 causes a motor generator to rotate the engine 102. In these embodiments, the electric machine 128 is a motor generator that is coupled to a power source, such as a battery (not shown), and the electric machine 128is coupled to the engine 102 via the shaft 126 (e.g., a drive shaft, an output shaft, etc.). In some embodiments, the shaft 126 is coupled to the engine 102 via one or more intermediate components, such as a clutch. The hydrogen purge circuit 214 is configured to cause the motor generator to rotate the engine at a predetermined engine speed. In some embodiments, the hydrogen purge circuit 214 is configured to cause the motor generator to rotate the engine 102 after stopping combustion. In some embodiments, the hydrogen purge circuit 214 is configured to cause the motor generator to rotate the engine 102 after the engine 102 stops rotating (e.g., after the engine speed is at or below a predetermined threshold, such as zero). In other embodiments, the hydrogen purge circuit 214 is configured to cause the motor generator to rotate the engine 102 before the engine 102 stops rotating (e.g., while the engine speed is at or above a predetermined threshold, such as zero). In some embodiments, the hydrogen purge circuit 214 is configured to cause the motor generator to rotate the engine 102 responsive to the hydrogen content value being at or above the threshold value.

[0091] In some embodiments, the hydrogen purge circuit 214 causes the motor generator to rotate the engine 102 for a predetermined number of rotations and / or for a predetermined amount of time.

[0092] In some embodiments, the hydrogen purge circuit 214 causes the air starter system 132 to rotate the engine 102. The hydrogen purge circuit 214 is configured to cause the air starter system 132 to rotate the engine at a predetermined engine speed (e.g., between approximately 200 RPM and 600 RPM). In some embodiments, the hydrogen purge circuit 214 is configured to cause the air starter system 132 to rotate the engine 102 after stopping combustion. In some embodiments, the hydrogen purge circuit 214 is configured to cause the air starter system 132 to rotate the engine 102 before the engine 102 stops rotating (e.g., while the engine speed is at or above a predetermined threshold, such as zero). In other embodiments, the hydrogen purge circuit 214 is configured to cause the air starter system 132 to rotate the engine 102 after the engine 102 stops rotating (e.g., after the engine speed is at or below a predetermined threshold, such as zero).(0093) In some embodiments, the hydrogen purge circuit 214 cause the IAT valve 114 to at least partially open during the shutdown procedure such that air flows through the intakeconduit 110 (e.g., past the at least partially open IAT valve 114), and into the engine 102 (e.g., via the intake manifold 112).

[0094] In any of the above-described embodiments, rotating the engine 102 causes one or more valves (e.g., the intake valve 160 and / or the exhaust valve 162) to actuate such that air (e.g., ambient air) is passed through the engine 102. As air passes through the engine 102, hydrogen is “purged” (e.g., displaced or moved) by the air and flows downstream (e.g., into the exhaust manifold, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120). In some embodiments, as air passes through the engine and / or through one or more of the downstream components (e.g., the exhaust manifold, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120) the air also purges hydrogen within one or more of the downstream components. For example, as the engine 102 is rotated, air passing through the engine is routed to the aftertreatment system 120 (e.g., via the exhaust manifold and / or the exhaust conduit 118) such that the air purges the hydrogen within the aftertreatment system 120. The purged hydrogen may flow out of the aftertreatment system 120 and to the atmosphere.

[0095] In some embodiments, the hydrogen purge circuit 214 is configured to enable or cause the air supply 115 during the shutdown procedure. In these embodiments, the air supply 115 is configured to provide air to flow through the engine 102. In this way, the air provided by the air supply 115 facilitates purging water from the engine 102 and / or a downstream component, such as one or more of the exhaust manifold 116, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120.

[0096] After completing the hydrogen purge procedure (e.g., after the engine 102 has rotated for the predetermined time period and / or after the engine 102 has rotated the number of predetermined rotations), the controller 140 may provide an indication that the hydrogen purge procedure is completed. In some embodiments, the controller 140 may provide the indication via the operator I / O device 130. In other embodiments, the controller 140 does not provide an indication that the hydrogen purge procedure is completed. In some embodiments, after the hydrogen purge procedure is completed, the controller 140 may receive an engine start request. The engine start request is described in greater detail herein above.

[0097] In some embodiments, the controller 140 may track a number of purge cycles performed. For example, the controller 140 may store in the memory device 206 a number of purges performed and a timestamp associated with when the purges occurred. In these embodiments, the controller 140 may selectively perform a purge when a shutdown occurs based on the number of purges performed recently (e.g., within a predetermined period of time). In this way, the controller 140 may periodically perform the purge such that a purge is not performed each time a shutdown occurs, but rather, the purge is performed selectively (e.g., every other shut down, every tenth shutdown, etc.).

[0098] FIG. 4 is a flow diagram of a method 300 of purging a fluid, such as water, from the engine system 100, according to an example embodiment. In particular, the controller 140 is structured to execute a shutdown procedure to purge a fluid from the engine 102 and / or the aftertreatment system 120. In some embodiments one or more of the processes of the method 300 are optional. For example, processes 302 and 304 are optional and may be omitted. In other embodiments, one or more of processes may be combined with one or more other depicted process. In still other embodiments, additional processes may be added to the method 300 without departing from the spirit and scope of the present disclosure.

[0099] At process 302, the controller 140 receives an engine start request. As described above, the engine start request may include one or more of an engine key on, an engine start button press, or other suitable engine start input. At process 304, the controller 140 operates the engine. For example, the controller 140 may operate the engine 102 according to one or more inputs as described above. As shown by the dotted lines in FIG. 3, in some embodiments, process 302 and process 304 are optional.

[0100] At process 306, the controller 140 receives an engine shutdown request. As described above, the engine shutdown request may include one or more of an engine key off, an engine stop button press, and / or other suitable engine stop input / command.

[0101] At process 308, the controller 140 executes a shutdown procedure. In some embodiments, the controller 140 executes the shutdown procedure responsive to receiving the engine shutdown request. In some embodiments, the engine shutdown procedure includes causing the engine 102 to continue to rotate (e.g., beyond normal shutdown rotations) by wayof one or more of (i) an increased engine inertia, (ii) the electric machine 128 including a battery powered starter and / or a battery powered motor or motor generator, and / or (iii) the air starter system 132. In some embodiments, the engine shutdown procedure includes causing the IAT valve 114 to at least partially open. In some embodiments, the engine shutdown procedure includes causing the air supply 115 to provide air to the engine 102. In some embodiments, the controller 140 may receive an indication that the engine 102 has stopped rotating and then cause rotation of the engine 102 after an initial stoppage of rotation. In this way, the stoppage of rotation may be the trigger condition for the controller 140 to continue to cause rotation of the engine 102. In any of the above-described embodiments, the controller 140 rotates the engine 102 and / or provides air to the engine 102 to purge a fluid, such as water, from the engine 102 and / or one or more downstream components, such as the exhaust manifold, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120. The purged fluid is carried by the air to an outlet of the aftertreatment system 120 and is vented into the atmosphere.101021 At process 310, the controller 140 provides a notification indicating that the engine shutdown procedure is completed. In some embodiments, the controller 140 may provide the notification to a remote computing device, such as a cloud computing system. In other embodiments, the controller 140 does not provide an indication that the engine shutdown procedure is completed.10.1031 In some embodiments, a user may manually initiate a purge. In some embodiments, the user may manually prevent a purge from occurring. In some embodiments, the user may indicate how often a purge should occur (e.g., every other shutdown, every fifth shutdown, etc.). In some embodiments, the notification may also indicate a number of purges performed recently and when the purges occurred. In this way the user may view the number of purges performed and when the purges occurred.10.1.041 FIG. 5 is a flow diagram of a method 400 of purging a fluid, such as hydrogen, from the engine system 100, according to an example embodiment. In particular, the controller 140 is structured to execute a fluid purge procedure to purge a fluid from the engine 102 and / or the aftertreatment system 120. In some embodiments one or more of the processes of the method 400 are optional. In other embodiments, one or more of processes may be combinedwith one or more other depicted process. In still other embodiments, additional processes may be added to the method 400 without departing from the spirit and scope of the present disclosure.

[0105] At process 402, the controller 140 receives an indication that an engine shutdown procedure is completed. In some embodiments, the indication is received from another component of the controller 140, such as the water purge circuit 212.|0106| At process 404, the controller 140 receives sensor data regarding a fluid content value. As described above, the fluid content value may include an amount or a concentration of a fluid, such as hydrogen, in the system 100 (e.g., at or proximate one or more components of the system 100, such as the engine 102 and / or the aftertreatment system 120). Thus, the controller 140 may receive information indicative of a hydrogen content value in an engine system. In an example embodiment, the fluid content value is a hydrogen content value at an outlet of the engine 102 and / or a hydrogen content value within the aftertreatment system 120. Still referring to process 404, the controller 140 may compare the fluid content value to a threshold value. If the fluid content value exceeds the threshold value (e.g., the fluid content value does not satisfy the threshold value), the method 400 continues to process 306. If the fluid content value is less than the threshold value (e.g., the fluid content value satisfies the threshold value), the method 400 continues to process 308.

[0107] At process 406, the controller 140 executes a fluid purge procedure. The fluid purge procedure may include causing the engine 102 to rotate by way of the electric machine 128 including a battery powered starter and / or a battery powered motor generator and / or the air starter system 132. In some embodiments, the fluid purge procedure includes causing the IAT valve 114 to at least partially open. In some embodiments, the fluid purge procedure includes causing the air supply 115 to provide air to the engine 102. In some embodiments, the controller 140 may receive an indication that the engine 102 has stopped rotating and execute the then cause rotation of the engine 102 after an initial stoppage of rotation. In this way, the stoppage of rotation may be the trigger condition for the controller 140 to continue to cause rotation of the engine 102. In any of the above-described embodiments, the controller 140 rotates the engine 102 and / or provides air to the engine 102 to purge a fluid, such as hydrogen, from the engine 102 and / or one or more downstream components, such as theexhaust manifold, the exhaust conduit 118, the turbo device 122, and / or the aftertreatment system 120. The purged fluid is carried by the air to an outlet of the aftertreatment system 120 and is vented into the atmosphere.

[0108] Still referring to process 406, in some embodiments, the controller 140 provides a notification indicating that the fluid purge procedure is completed. In other embodiments, the controller 140 does not provide an indication that the fluid purge procedure is completed.101091 In some embodiments, the controller 140 may track a number of purge cycles performed. For example, the controller 140 may store in the memory device 206 a number of purges performed and a timestamp associated with when the purges occurred. In these embodiments, the controller 140 may selectively perform a purge when a shutdown occurs based on the number of purges performed recently (e.g., within a predetermined period of time). In this way, the controller 140 may periodically perform the purge such that a purge is not performed each time a shutdown occurs, but rather, the purge is performed selectively (e.g., every other shut down, every tenth shutdown, etc.).

[0110] At process 408, the controller 140 receives an engine start request. As described above, the engine start request may include one or more of an engine key on, an engine start button press, or other suitable engine start input. Responsive to receiving the engine start request, the controller 140 may cause the engine 102 to start by enabling an electric starter, such as the electric machine 128, enabling the fuel system 124 to deliver fuel to the cylinders 104, enabling the I AT valve 114 to provide air to the cylinders 104, and / or enabling the igniters 106 to ignite an air / fuel mixture within the cylinders 104.

[0111] 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 inconsequentialmodifications 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.

[0112] 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).

[0113] 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).

[0114] 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.

[0115] While various circuits with particular functionality are shown in FIG. 3, it should be understood that the controller 140 may include any number of circuits for completing thefunctions described herein. For example, the activities and functionalities of the water purge circuit 212 and / or the hydrogen purge circuit 214 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.

[0116] 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.

[0117] 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 ormore 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.

[0118] 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.

[0119] 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 acomputer 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.

[0120] 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.

[0121] 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).

[0122] 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.

[0123] 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 specifieddifferently 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.

[0124] 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.

Claims

WHAT IS CLAIMED IS:

1. A system comprising: a controller communicably coupled to a hydrogen fueled internal combustion engine, the controller comprising at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations comprising: receiving an engine shutdown request; and responsive to receiving the engine shutdown request, executing an engine shutdown procedure comprising causing the hydrogen fueled internal combustion engine to continue to rotate for at least a predetermined number of rotations or at least a predetermined time period.

2. The system of claim 1, wherein executing the engine shutdown procedure further comprises: causing the hydrogen fueled internal combustion engine to increase an engine speed to a predetermined engine speed; and causing a fuel system to cease supply of hydrogen fuel to the hydrogen fueled internal combustion engine.

3. The system of claim 2, wherein causing the fuel system to cease the supply of the hydrogen fuel to the hydrogen fueled internal combustion engine is responsive to the engine speed being at or above the predetermined engine speed.

4. The system of claim 3, wherein the predetermined engine speed corresponds to the predetermined number of rotations or the predetermined time period, such that when the fuel system ceases supply of the hydrogen fuel to the hydrogen fueled internal combustion engine after the engine speed is at or above the predetermined engine speed, the hydrogen fueled internal combustion engine continues to rotate for at least the predetermined number of rotations or at least the predetermined time period.

5. The system of claim 1 further comprising an electric machine coupled to the engine and operable to rotate the engine, wherein the controller is coupled to the electric machine to cause operation of the electric machine to rotate the engine.

6. The system of claim 5, wherein the electric machine is an electric starter; and wherein executing the engine shutdown procedure by the controller comprises: causing a fuel system to cease supply of hydrogen fuel to the hydrogen fueled internal combustion engine; receiving data indicative of a current engine speed; and causing the electric starter to rotate the engine at a first engine speed responsive to the current engine speed being at or below the first engine speed.

7. The system of claim 6, wherein executing the engine shutdown procedure by the controller comprises causing the electric starter to sync the current engine speed with an electric starter speed, such that the electric starter rotates the engine at the first engine speed responsive to the current engine speed being at the first engine speed.

8. The system of claim 5, wherein the electric machine is a motor generator; and wherein executing the engine shutdown procedure by the controller comprises: causing a fuel system to cease supply of hydrogen fuel to the hydrogen fueled internal combustion engine; and causing the motor generator to rotate the engine at a first engine speed.

9. The system of claim 8, wherein executing the engine shutdown procedure by the controller comprises causing the motor generator to rotate the engine after causing the fuel system to cease supply of the hydrogen fuel to the hydrogen fueled internal combustion engine.

10. The system of claim 8, wherein executing the engine shutdown procedure by the controller comprises causing the motor generator to rotate the engine prior to causing the fuel system to cease supply of the hydrogen fuel to the hydrogen fueled internal combustion engine.

11. The system of claim 8, wherein executing the engine shutdown procedure by the controller comprises causing the motor generator to rotate the engine responsive to an engine speed being at or below a predetermined engine speed.

12. The system of claim 8, wherein executing the engine shutdown procedure by the controller comprises causing the motor generator to rotate the engine responsive to an engine speed being above a predetermined engine speed.

13. An engine system comprising: a controller communicably coupled to an engine configured to combust hydrogen fuel and an electric machine coupled to the engine, the controller comprising at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations comprising: receiving information indicative of a hydrogen content value in the engine system; comparing the hydrogen content value to a threshold value; and responsive to determining that the hydrogen content value exceeds the threshold value, executing a fluid purge procedure including: causing the electric machine to rotate the engine for at least a predetermined number of rotations or at least a predetermined time period.

14. The system of claim 13, wherein the electric machine is an motor generator, wherein executing the fluid purge procedure by the controller comprises causing the motor generator to rotate the engine at a first engine speed.

15. The system of claim 13, wherein the electric machine is an electric starter, wherein executing the fluid purge procedure by the controller comprises causing the electric starter to rotate the engine at a first engine speed.

16. The system of claim 13, further comprising a forced air supply configured to provide air to the engine, wherein executing the fluid purge procedure by the controller further comprises: causing an intake valve of the engine to at least partially open; and causing the forced air supply to provide the air to the engine.

17. The system of claim 13, wherein executing the fluid purge procedure by the controller is responsive to a speed of the engine being at or below a predetermined threshold.

18. The system of claim 13, wherein the instructions, when executed by the at least one processor, cause the controller to perform further operations comprising: storing, in the at least one memory device, a number of fluid purge procedures performed within a predetermined period of time; and executing the fluid purge procedure responsive to the number of the fluid purge procedures performed within the predetermined period of time being at or below a predetermined threshold.

19. A system comprising: a controller communicably coupled to an engine configured to combust hydrogen fuel and a compressed air system coupled to at least one of the engine or an air starter, the controller comprising at least one processor coupled to at least one memory device storing instructions that, when executed by the at least one processor, cause the controller to perform operations comprising: causing the compressed air system to rotate the engine for at least one of: a predetermined number of rotations, a predetermined time period, a predetermined number of combustion events, or until a speed of the engine exceeds a predetermined threshold.

20. The system of claim 19, further comprising a fuel system coupled to the engine and configured to provide the hydrogen fuel to the engine; and wherein the controller is coupled to the fuel system, and the operations further comprise causing the fuel system to provide the hydrogen fuel to the engine after the compressed air system has started rotating the engine.

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