Transient response strategy for hydrogen fueled internal combustion engines

Abstract

Systems, methods, and apparatuses are disclosed that determine a post injection fueling condition in response to one or more engine operating parameters. In response to the post injection fueling condition being present, one of a transient response mode or a thermal management mode is selected in order to determine a post injection fueling amount from a transient response fueling table or a thermal management fueling table. The transient response mode is selected in response to the lambda amount being less than a lambda threshold, and the thermal management mode is selected in response to the lambda amount being less than the lambda threshold and an aftertreatment temperature being less than a temperature threshold.

Description

Atty Docket No CMI002-00180 / 24-0031 -SRCTRANSIENT RESPONSE STRATEGY FOR HYDROGEN FUELED INTERNALCOMBUSTION ENGINESCross-Reference to Related Application;

[0001] The present application claims priority to Chinese Patent Application No. 202411199946.5 filed August 29, 2024, which is incorporated herein by reference.Field of the Invention:

[0002] The present application is related to internal combustion engines, and more particularly to a transient response strategy for hydrogen fueled internal combustion engines.BACKGROUND

[0003] For hydrogen fueled internal combustion engines, a lean bum strategy is used to control knock boundaries and provide a higher brake thermal energy (BTE) target. During transient responses of the engine, the air-fuel ratio (lambda) reduces quickly to rich bum area, such as to transient lambdas ranging from 1.0 to 1.2. This transient response increases fueling to meeting the output demand for the engine, but also increases the risk for knock and for higher engine out nitrogen oxides (NOx).

[0004] One technique for mitigating NOx generation during combustion is to maintain the aftertreatment temperature in a region that provide the desired conversion efficiency for NOx mitigation. However, during transient operating conditions, the intake throttle is occupied in providing the air flow requirement needed to meet the transient response output torque requirements for the engine. Thus, the intake throttle is not able to be employed for thermal management of the aftertreatment components during a transient response without reducing the stability of combustion. Therefore, further improvements in this technological area are needed.Atty Docket No CMI002-00180 / 24-0031 -SRCSUMMARY

[0005] The present application includes systems, methods, and apparatuses that determine a post injection fueling condition is present in response to one or more engine operating parameters while a lean bum spark ignited internal combustion engine is operating. The one or more operating parameters include an air-fuel ratio, or lambda amount, and an aftertreatment temperature, such as SCR inlet temperature. The internal combustion engine nominally operates using a base injection fuel amount in one or more combustion chambers in a base fueling mode unless a post injection fueling condition is determined to be present. The presence of the post injection fueling condition results in the selection of a post injection fueling mode based on the lambda amount and the aftertreatment temperature.

[0006] For example, a transient response mode is activated in response to the lambda amount being less than a first lambda threshold associated with an engine transient. A thermal management mode is activated in response to the aftertreatment temperature being less than a first temperature threshold associated with a desired NOx conversion efficiency and the lambda amount being less than the first lambda threshold. In response to the activated post injection fueling mode, such as the transient response mode or the thermal management mode, a post injection fuel amount is selected from a fuel table corresponding to the activated post injection fueling mode. A post injection fuel amount from the selected fuel table and is injected for combustion in the one or more combustion chambers in addition to the base injection fuel amount. Combustion of the post injection fuel amount is timed so less work is extracted from it as compared to the base injection fuel amount by the piston, and more energy is sent to the exhaust to produce a positive airflow response from the turbocharger to improve engine performance and / or to increase the aftertreatment temperature using post fuel injection amounts without producing fuel slip into the exhaust or aftertreatment.

[0007] This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. Further embodiments, forms, objects, features, advantages, aspects, and benefits shall become apparent from the following description and drawings.Atty Docket No CMI002-00180 / 24-0031 -SRCBRIEF DESCRIPTION OF THE DRAWINGS

[0008] The description herein makes reference to the accompanying figures wherein like reference numerals refer to like parts throughout the several views.

[0009] FIG. 1 illustrates a schematic block diagram of an exemplary internal combustion engine system that includes a lean bum spark ignition internal combustion engine.

[0010] FIG. 2 illustrates a block diagram of certain components of an exemplary controller used to control certain operations of components of the engine system of FIG. 1 in a base mode, transient response mode, and thermal management mode.

[0011] FIG. 3 is a schematic illustration of an exemplary post injection fueling table.

[0012] FIG. 4 is a graphical illustration of activation and deactivation of the transient response mode over time.

[0013] FIG. 5 is a graphical illustration of activation and deactivation of the thermal management mode over time.

[0014] FIG. 6 illustrates a flow diagram of an exemplary process of operation of the engine system of FIG. 1 to provide a post injection fuel amount for combustion for transient response or thermal management along with abase injection fuel amount.

[0015] The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, certain embodiments. It should be understood, however, that the present invention is not limited to the arrangements and instrumentalities shown in the attached drawings. Further, like numbers in the respective figures indicate like or comparable parts.Atty Docket No CMI002-00180 / 24-0031 -SRCDESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0016] Certain terminology is used in the foregoing description for convenience and is not intended to be limiting. Words such as “upper,” “lower,” “top,” “bottom,” “first,” and “second” designate directions in the drawings to which reference is made. This terminology includes the words specifically noted above, derivatives thereof, and words of similar import. Additionally, the words “a” and “one” are defined as including one or more of the referenced item unless specifically noted. The phrase “at least one of’ followed by a list of two or more items, such as “A, B or C,” means any individual one of A, B or C, as well as any combination thereof.

[0017] Embodiments of the present application include a control strategy and method that can improve lean bum spark ignited internal combustion engine performance to better respond to transient conditions while providing NOx mitigation. A post injection fuel amount is determined for injection in addition to a base injection fuel amount that are both fully combusted during the engine cycle but at different timings so the post injection fuel amount contributes energy to the exhaust flow rather than to the piston to increase turbine output and / or aftertreatment temperature.

[0018] FIG. 1 illustrates a schematic block diagram of an exemplary internal combustion engine system 100 that includes a lean bum spark ignition internal combustion engine 102 that is connected to an intake 104 and an exhaust 106. It shall be appreciated that the illustrated configuration and components of the engine system 100 are but one example, and that the disclosure contemplates that a variety of different engine systems and the associated components may be utilized. Further, the engine system 100 may be used in a variety of different applications or platforms, and moreover with a variety of different types of machines, vehicles, and / or devices, including, but not limited to, stationary devices as well as on-road vehicles, including automotive applications.

[0019] Engine 102 can receive fuel from one or more fuel sources 108 that include hydrogen fuel. Further, while the illustrated embodiment may generally depict an engine system 100 used with lean bum spark ignition engine applications powered by gaseous hydrogen fuel, the engine system 100 can be structured to operate with a variety of types of fuels that are delivered from the fuel source 108, including, for example, gaseous fuels such as hydrogen, natural gas, biogas, methane, propane, gasoline, ethanol, producer gas, field gas, liquefied natural gas, compressed natural gas, landfill gas, gaseous fuel, and / or any combination thereof, among other fuels.Atty Docket No CMI002-00180 / 24-0031 -SRC

[0020] According to the exemplary embodiment, the engine 102 includes an engine block that may define at least a portion of one or more cylinders 110. For example, according to certain embodiments, the engine 102 can include six cylinders 110 in an in-line arrangement as illustrated in FIG. 1. However, the engine 102 may have any different number of cylinders 110, as well as cylinders in a variety of different arrangements. Additionally, each cylinder 110 is sized to accommodate the slideable displacement of a piston (not shown) along at least a portion of the cylinder 110 such that the pistons may reciprocate between a top-dead-center position and a bottom-dead-center position. Each of the cylinders 110, its respective piston and cylinder head, form a combustion chamber. Further, at least a portion of the forces generated by the slideable displacement of the piston along at least a portion of the cylinder during combustion events in the combustion chamber are transmitted to a mechanical drive system (not shown.) For example, the pistons are typically operably coupled to a crank shaft of the engine system 100 that converts the reciprocal movement of the pistons of the engine 102 into rotational movement.

[0021] The cylinders 110 are in selective fluid communication with the intake 104 such that a charged air flow can be delivered to the combustion chamber. The cylinders 110 are also in selective fluid communication with the exhaust 106 such that exhaust gases produced by combustion of fuel(s) in the combustion chambers can be delivered through an exhaust manifold 112 of the exhaust 106. The exhaust 106 can include and / or be coupled to a variety of different components, such as, for example, one or more turbines 114a of turbocharger 114, as well as an aftertreatment system 116. Engine system 100 may also include an exhaust gas recirculation system (not shown), such as a high pressure and / or a low pressure exhaust gas recirculation system.

[0022] Operation of fuel injection events can include the delivery of charge flow and fuel to the combustion chambers of the engine 102. According to certain embodiments, gaseous fuel can be injected into each cylinder 110 via a corresponding one of the injectors 120. Other embodiments contemplate gaseous fuel is fumigated into the charge flow upstream of the cylinders 110 of engine 102, such as, for example, upstream or downstream of the compressor 114b of turbocharger 144 at intake 104, at the intake manifold 118, and / or cylinder ports, or can be fumigated into the charge mixture in-cylinder. Combustion of the air-fuel mixture can be initiated with igniters 122, such as spark plugs, that create a spark at each of the cylinders 110. The delivery of the charge mixture, the fuel, and / or the ignition of the charge and fuel mixture in the combustionAtty Docket No CMI002-00180 / 24-0031 -SRC chambers may be, at least in part, electrically controlled by an electronic control system 130 of the engine system 100, as discussed further below.

[0023] In an embodiment, engine 102 includes pistons that reciprocate in the corresponding cylinders 110 during a four stroke cycle in which a crankshaft rotates 720 degrees per cycle. The term “four stroke” herein means the following four strokes - intake, compression, power, and exhaust - that the piston completes during two separate revolutions of the engine’s crankshaft, which is a combustion cycle. A stroke begins either at a top dead center (TDC) when the piston is at the top of cylinder, or at a bottom dead center (BDC), when the piston has reached its lowest point in the cylinder.

[0024] During the intake stroke, the piston descends away from cylinder head above the combustion chamber of the cylinder 110 to a bottom (not shown) of the cylinder 110, thereby reducing the pressure in the combustion chamber. A combustion charge is created in the combustion chamber by an intake of a charge from intake 104 through intake ports when the intake valves are opened.

[0025] During the compression stroke in a nominal or standard mode of operation, the intake valves and the exhaust valves are closed. The piston returns toward TDC and fuel is injected near TDC in a base injection event, and the compressed fuel-air mixture ignites in the combustion chamber after a short delay. The ignition of the air and fuel causes a rapid increase in pressure in the combustion chamber, which is applied to the piston during its power stroke toward the BDC. Combustion phasing in combustion chamber is calibrated so that the increase in pressure in combustion chamber due to injection of a base fuel amount for the base injection event pushes the piston, providing a net positive in the force / work / power of the piston to rotate the crankshaft.

[0026] As discussed further below, during certain operating conditions of engine 102, a post injection fueling condition is indicated and a post injection fueling mode is selected to determine a post injection fuel amount for injection during the injection event after injection and combustion of the base injection fuel amount. The fuel provided for the post injection fuel amount is injected at a timing so that its combustion during the current combustion cycle provides less force / work / power to the piston than the base injection fuel amount and more energy is directed to the exhaust 106 to increase turbine output.Atty Docket No CMI002-00180 / 24-0031 -SRC

[0027] During the exhaust stroke, the piston is returned toward TDC while the exhaust valves are open. This action discharges the burnt products of the combustion of the fuel in the combustion chamber and expels the spent fuel-air mixture (exhaust gas) out through the exhaust valves into exhaust 106. The next combustion cycle occurs using these same intake and exhaust valve opening closing profiles, unless a cylinder deactivation condition or alternative valve lift condition is employed.

[0028] The control system 130 can include an electronic controller or electronic control unit (ECU) 132 that can be configured to control various operational aspects of engine system 100, including fuel injection events and spark events, among other operations. The electronic controller 132 can be implemented in a number of ways. Further, the electronic controller 132 can execute operating logic that defines various control, management, and / or regulation functions. The operating logic may be in the form of one or more microcontroller or microprocessor routines stored in a non-transitory memory, dedicated hardware, such as a hardwired state machine, analog calculating machine, various types of programming instructions, and / or other forms as would occur to those skilled in the art.

[0029] The controller 132 may be provided as a single component, or a collection of operatively coupled components, and may comprise digital circuitry, analog circuitry, or a hybrid combination of both of these types. When of a multi-component form, the controller 132 may have one or more components remotely located relative to the others in a distributed arrangement. The controller 132 can include multiple processing units arranged to operate independently, in a pipeline processing arrangement, in a parallel processing arrangement, or the like. In one embodiment, the controller 132 includes several programmable microprocessing units of a solid- state, integrated circuit type that are distributed throughout the engine system 100 that each includes one or more processing units and non-transitory memory.

[0030] For the depicted embodiment, the controller 132 includes a computer network interface to facilitate communications using standard Controller Area Network (CAN) communications or the like among various system control units. It should be appreciated that the depicted modules or other organizational units of the controller 132 refer to certain operating logic performing indicated operations that may each be implemented in a physically separate controller of the controller 132 and / or may be virtually implemented in the same controller. Controller 132 may include one or more organizational units or circuits that may be implemented in hardwareAtty Docket No CMI002-00180 / 24-0031 -SRC and / or as computer instructions on a non-transient computer readable storage medium, and may be distributed across various hardware or computer based components.

[0031] Example and non-limiting implementation elements of control system 130 and / or organizational units of the controller 132 include, for example, sensors such as intake sensors 134, engine sensors 136, exhaust sensors 138, and / or other sensors providing any value determined herein, sensors providing any value that is a precursor to a value determined herein, datalink and / or network hardware including communication chips, oscillating crystals, communication links, cables, twisted pair wiring, coaxial wiring, shielded wiring, transmitters, receivers, and / or transceivers, logic circuits, hard-wired logic circuits, reconfigurable logic circuits in a particular non-transient state configured according to the module specification, any actuator including at least an electrical, hydraulic, or pneumatic actuator, a solenoid, an op-amp, analog control elements (springs, filters, integrators, adders, dividers, gain elements), and / or digital control elements. Sensors 134, 136, 138 and / or any other sensors may be physical sensors, virtual sensors, and / or combinations of physical and virtual sensors.

[0032] The controller 132 and / or any of its constituent processors / controllers may include one or more signal conditioners, modulators, demodulators, Arithmetic Logic Units (ALUs), Central Processing Units (CPUs), limiters, oscillators, control clocks, amplifiers, signal conditioners, filters, format converters, communication ports, clamps, delay devices, memory devices, Analog to Digital (A / D) converters, Digital to Analog (D / A) converters, and / or different circuitry or functional components as would occur to those skilled in the art to perform the desired communications.

[0033] Referencing FIG. 2, according to certain embodiments, electronic controller 132 includes a base fuel amount determination circuit 140, a first post injection mode determination circuit 142, and a second post injection mode determination circuit 144. The circuits 140, 142, 144 operate to determine an amount and timing of one or more injections of fuel into cylinders 110. Circuits 140, 142, 144 may also determine one or more spark timings to fully combust the delivered fuel during the current combustion cycle to prevent fuel slip into the exhaust,

[0034] First post injection mode determination circuit 142 receives a number of lambda related inputs 148 that are used to determine air-fuel ratios. The air-fuel ratios are input to a stoichiometric transfer function 150 to output a lambda amount 152. Lambda related inputs 148 can be, for example, an intake air flow rate or charge flow 154, a total fueling 156, and otherAtty Docket No CMI002-00180 / 24-0031 -SRC parameters that might be used in determining the inputs to stoichiometric transfer function 150 and / or lambda amount, such as a requested torque output, an engine speed, a current gear, and other parameters.

[0035] The lambda amount 152 is input to a decision node 158 of first post injection mode determination circuit 142. Decision node 158 evaluates whether the lambda amount 152 is less than a first lambda threshold. If decision node 158 outputs YES, first post injection mode determination circuit 142 activates a transient response mode (TRM) 160. Activation of the transient response mode 160 directs the determination of the post injection fuel amount 164 to be based on a transient response fueling table 162. The post injection fuel amount 164 selected from transient response fueling table 162 can be determined, for example, based on the speed and load of engine 102.

[0036] The first lambda threshold at decision node 158 is indication of a transient event. A transient event can occur, for example, due to depression of an input device requesting an increase in engine output such as an accelerator tip-in event, a threshold increase in load applied to engine 102, a threshold increase in power demanded from engine 102, and / or a threshold increase in torque in an output shaft connected to engine 102. In addition or alternatively, one or more sensors connected to controller 132 can be operable to provide operating signals indicating one or more operating parameters or conditions of engine 102 that indicate a current or predicted transient event.

[0037] Second injection mode determination circuit 144 also receives the lambda amount 152. In addition, second mode determination circuit 144 receives an aftertreatment temperature input 170. Aftertreatment temperature input 170 can be a temperature condition of the exhaust flow and / or one or more components of aftertreatment system 116. In an embodiment, the aftertreatment temperature input 170 is an inlet temperature of an SCR catalyst. However, aftertreatment temperature input can be any temperature input that is indicative of a NOx conversion efficiency of aftertreatment system 116.

[0038] The lambda amount 152 and aftertreatment temperature input 170 are received by decision node 172 of second post injection mode determination circuit 144. Decision node 172 evaluates whether the lambda amount 152 is less than the first lambda threshold and whether the aftertreatment temperature input 170 is less than a first temperature threshold associated with a desire NOx conversion efficiency. If decision node 172 outputs YES, second post injection modeAtty Docket No CMI002-00180 / 24-0031 -SRC determination circuit 144 activates a thermal management (TM) mode 174. Activation of thermal management mode 174 directs the determination of the post injection fuel amount 178 to be based on a thermal management fueling table 176. The post injection fuel amount 178 from thermal management fueling table 176 can be selected or determined based on the speed and load of engine 102.

[0039] If decision node 158 and decision node 170 output NO, base fuel amount determination circuit 140 activates base mode 180, and the transient response mode 160 and thermal management mode 174 are disabled at output 182. Base mode 180 determines a base injection fuel amount to be injected based on engine speed and engine load without a post injection for a transient response and / or thermal management. The base injection fuel amount is an amount of fuel injected into the combustion chamber in the absence of the post injection fueling condition. The base injection fuel amount is also determined while the transient response mode 160 and thermal management mode 174 are active, and the post injection fuel amount 164, 178 is provided after the base injection fuel amount.

[0040] Electronic controller 132 can further be configured to determine a start of base injection timing and an end of base injection timing for the base injection fuel amount. When the transient response mode 160 or thermal management mode 174 are active, electronic controller 132 also determines a start of post injection timing and an end of post injection timing for the post injection fuel amount.

[0041] Electronic controller 132 can also be configured to determine a base spark timing to combust the base injection fuel amount and a post spark timing to combust the post injection fuel amount 164 or 178. The post spark timing and start and end of post injection timing of the post injection event are timed so combustion of the post injection fuel amount 164 or 178 during the combustion cycle provides less energy to the piston and more energy to the exhaust than the base injection fuel amount.

[0042] FIG. 3 provides a graphical example of a transient response fueling table 162 and a thermal management fueling table 176. Fueling tables 162, 176 can be separate tables, or integrated as a post fueling table 300 as shown in FIG. 3. The post fueling table 300 includes transient response region 302 based on the speed and load of engine 102. Post fueling table 300 also includes a thermal management region 304 based on the speed and load of engine 102. Transient response region 302 and thermal management region 304 overlap in overlap region 306.Atty Docket No CMI002-00180 / 24-0031 -SRCA base region 308 is provided outside of transient response region 302 and thermal management region 304 in which a base injection fuel amount only is provided for fueling of engine 102 without a post injection fuel amount.

[0043] In the example table of FIG. 3, the transient response region 302 of transient response mode 162 provides a post injection fuel amount to supplement the base injection fuel amount over a wider range of engine speeds but a lower range of engine loads than thermal management mode 174. In contrast, the thermal management region 304 of thermal management mode 174 provides a post injection fuel amount to supplement the base injection fuel amount over a wider range of engine loads but a lower range of engines speeds than transient response mode 162.

[0044] FIG. 4 provides a graphical illustration 400 of activating and deactivating the transient response mode 160 over time. For example, a first lambda threshold 402 and a second lambda threshold 404 are shown along with lambda amount 152 over time. When lambda amount 152 is less than first lambda threshold 402, the transient response mode 160 is activated. When lambda amount 152 is greater than second lambda threshold 404, the transient response mode 160 is deactivated. In an embodiment, first lambda threshold 402 is less than the second lambda threshold 404. In an embodiment, first lambda threshold 402 is 1.6 and second lambda threshold 404 is 1.8. Other embodiments contemplate other lambda values for the first and second thresholds.

[0045] FIG. 5 provides a graphical illustration 500 of activating and deactivating the thermal management mode 174 over time. For example, a first temperature threshold 502 and a second temperature threshold 504 are shown along with aftertreatment temperature input 170 over time. When aftertreatment temperature input 170 is less than first temperature threshold 502 (and lambda amount 152 is less first lambda threshold 402), the thermal management mode 174 is activated. When aftertreatment temperature input 170 is greater than second temperature threshold 504, the thermal management mode 174 is deactivated. In an embodiment, first temperature threshold 502 is less than second temperature threshold 504. In an embodiment, first temperature threshold 502 is 100 degrees Celsius and second temperature threshold 504 is 120 degrees Celsius. Other embodiments contemplate other temperature values for the first and second thresholds.

[0046] Referring to FIG. 6, a schematic flow diagram of a procedure 600 is provided. Procedure 600 determines an amount and timing of one or more injections of fuel into cylindersAtty Docket No CMI002-00180 / 24-0031 -SRC110, and one or more spark timings to fully combust the delivered fuel during the current combustion cycle to prevent fuel slip into the exhaust.

[0047] Procedure 600 starts at 602, and continues at operation 604 to monitor engine operating parameters while operating engine 102. Procedure 600 continues at conditional 606 to determine if a post injection fueling condition is present from the one or more operating parameters. If conditional 606 is NO, procedure 600 returns to operation 604 an continues to monitor for a post injection fueling condition. If conditional 606 is YES, a post injection condition is present and procedure 600 continues at conditional 608.

[0048] In an embodiment, conditional 606 is affirmative or YES when the one or more operating parameters indicate a transient condition for engine 102 is present. For example, the one or more operating conditions indicating the transient condition is present can be a lambda amount 152 that is less than a first lambda threshold 402. Other embodiments contemplate that other operating states of engine 102 indicated by the operating parameters may indicate a transient condition that requires a post injection fueling event.

[0049] At conditional 608, procedure 600 determines if an aftertreatment temperature is less than a first temperature threshold. For example, conditional 608 can evaluate aftertreatment temperature input 170 with first temperature threshold 502. If conditional 608 is NO, procedure 600 continues at operation 610 to activate the transient response mode 160. If conditional 608 is YES, procedure 600 continues at operation 612 and activates the thermal management mode 174. Procedure 600 continues at operation 614 to determine the post injection fuel amount based on the activated mode 160 or 172.

[0050] As discussed above, activation of the transient response mode 160 at operation 610 results in the post injection fuel amount 164 being determined at operation 614 from transient response fueling table 162 and / or transient response region 302. Activation of thermal management mode 174 at operation 612 results in the post injection fuel mount 178 being determined at operation 614 from thermal management fueling table 176 and / or thermal management region 304. The post injection fuel amount is in addition to the base injection fuel amount, and both are injected into the combustion chamber of a cylinder 110 of engine 102 during the combustion cycle for the combustion chamber.

[0051] Procedure 600 may also include determining a start-of-inj ection (SOI) and end-of- injection (EOI) for each of the base injection fuel amount and the post injection fuel amount.Atty Docket No CMI002-00180 / 24-0031 -SRCProcedure 600 may further include determining a spark timing that fully combusts the base injection fuel amount and the post injection fuel amount during the combustion cycle. In an embodiment, a second or post spark timing is provided to produce a second spark for the post injection fuel amount combustion.

[0052] Various aspects of the present disclosure are contemplated. For example, according to one aspect a system for controlling combustion in an internal combustion engine is provided. The system includes an electronic controller configured to determine a post injection fueling condition is present for the internal combustion engine in response to a lambda amount during operation of the internal combustion engine. In response to the post injection fueling condition being present, the electronic controller is configured to activate a transient response mode in response to the lambda amount being less than a first lambda threshold, or activate a thermal management mode in response to the lambda among being less than the first lambda threshold and an aftertreatment temperature being less than a first temperature threshold associated with a desired NOx conversion efficiency. The electronic controller is configured to select a post injection fuel amount from a transient response fueling table or from a thermal management fueling table depending on whether the transient response mode is activated or the thermal management mode is activated, and inject a base injection fuel amount and the post injection fuel amount after injection of the base injection fuel amount into a combustion chamber of the internal combustion engine during a combustion cycle of the internal combustion engine.

[0053] In an embodiment, the electronic controller is further configured to determine a start of base injection timing and an end of base injection timing for the base injection fuel amount. The electronic controller is also configured to determine a start of post injection timing and an end of post injection timing for the post injection fuel amount.

[0054] In a further embodiment, the electronic controller is further configured to determine a base spark timing to combust the base injection fuel amount and a post spark timing to combust the post injection fuel amount.

[0055] In a further embodiment, the post spark timing and the start and end of post injection timing of the post injection fuel amount are timed so combustion of the post injection fuel amount during the combustion cycle provides less energy to the piston and more energy to the exhaust than the base injection fuel amount.Atty Docket No CMI002-00180 / 24-0031 -SRC

[0056] In an embodiment, the base injection fuel amount is an amount of fuel injected into the combustion chamber in the absence of the post injection fueling condition.

[0057] In an embodiment, the aftertreatment temperature is an inlet temperature of a selective catalytic reduction (SCR) catalyst.

[0058] In a further embodiment, the thermal management mode remains active until the inlet temperature of the selective catalytic reduction catalyst is greater than a second temperature threshold.

[0059] In a further embodiment, the first temperature threshold is 100 degrees Celsius and the second temperature threshold is 120 degrees Celsius.

[0060] In an embodiment, the transient response mode remains active until the lambda amount is greater than a second lambda threshold that is more than the first lambda threshold.

[0061] In a further embodiment, the first lambda threshold is 1.6 and the second lambda threshold is 1.8.

[0062] In an embodiment, the system includes the internal combustion engine. The internal combustion engine includes a plurality of cylinders for receiving an intake air flow and fuel, a plurality of spark plugs associated with respective ones of the plurality of cylinders, and a turbocharger that compresses the intake air flow using exhaust produced by combustion in the plurality of cylinders.

[0063] According to another aspect of the present disclosure, a method for controlling combustion in an internal combustion engine is provided. The method includes determining a post injection fueling condition is present for the internal combustion engine in response to a lambda amount during operation of the internal combustion engine; in response to the post injection fueling condition, activating either a transient response mode in response to the lambda amount being less than a first lambda threshold or activating a thermal management mode in response to the lambda among being less than the first lambda threshold and an aftertreatment temperature being less than a first temperature threshold associated with a desired NOx conversion efficiency; selecting a post injection fuel amount from a transient response fueling table or from a thermal management fueling table depending on whether the transient response mode or the thermal management mode is activated; and injecting a base injection fuel amount and the post injection fuel amount after injecting the base injection fuel amount into aAtty Docket No CMI002-00180 / 24-0031 -SRC combustion chamber of the internal combustion engine during a combustion cycle of the internal combustion engine.

[0064] In an embodiment, the method includes determining a base spark timing to combust the base injection fuel amount and a post spark timing to ignite the post injection fuel amount.

[0065] In an embodiment, the base injection fuel amount is an amount of fuel injected into the combustion chamber in the absence of the post injection fueling condition.

[0066] In an embodiment, the post injection fueling condition is present in response to a transient operating condition of the internal combustion engine.

[0067] In an embodiment, the aftertreatment temperature is an inlet temperature of a selective catalytic reduction (SCR) catalyst.

[0068] In a further embodiment, the thermal management mode remains active until the inlet temperature of the selective catalytic reduction catalyst is greater than a second temperature threshold.

[0069] In a further embodiment, the first temperature threshold is 100 degrees Celsius and the second temperature threshold is 120 degrees Celsius.

[0070] In an embodiment, the transient response mode remains active until the lambda amount is greater than a second lambda threshold that is more than the first lambda threshold.

[0071] In a further embodiment, the first lambda threshold is 1.6 and the second lambda threshold is 1.8.

[0072] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the invention, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is noAtty Docket No CMI002-00180 / 24-0031 -SRC intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and / or “a portion” is used the item may include a portion and / or the entire item unless specifically stated to the contrary.

Claims

Atty Docket No CMI002-00180 / 24-0031 -SRCWHAT IS CLAIMED IS:

1. A system for controlling combustion in an internal combustion engine, the system comprising: an electronic controller configured to: determine a post injection fueling condition is present for the internal combustion engine in response to a lambda amount during operation of the internal combustion engine; in response to the post injection fueling condition being present, activate a transient response mode in response to the lambda amount being less than a first lambda threshold or activate a thermal management mode in response to the lambda amount being less than the first lambda threshold and an aftertreatment temperature being less than a first temperature threshold associated with a desired NOx conversion efficiency; select a post injection fuel amount from a transient response fueling table or from a thermal management fueling table depending on whether the transient response mode is activated or the thermal management mode is activated; and inject a base injection fuel amount and the post injection fuel amount after injection of the base injection fuel amount into a combustion chamber of the internal combustion engine during a combustion cycle of the internal combustion engine.

2. The system of claim 1, wherein the electronic controller is configured to: determine a start of base injection timing and an end of base injection timing for the base injection fuel amount; and determine a start of post injection timing and an end of post injection timing for the post injection fuel amount.

3. The system of claim 2, wherein the electronic controller is further configured to determine a base spark timing to combust the base injection fuel amount and a post spark timing to combust the post injection fuel amount.

4. The system of claim 3, wherein the post spark timing and the start and end of post injection timing of the post injection fuel amount are timed so combustion of the post injectionAtty Docket No CMI002-00180 / 24-0031 -SRC fuel amount during the combustion cycle provides less energy to the piston and more energy to the exhaust than the base injection fuel amount.

5. The system of claim 1, wherein the base injection fuel amount is an amount of fuel injected into the combustion chamber in the absence of the post injection fueling condition.

6. The system of claim 1, wherein the aftertreatment temperature is an inlet temperature of a selective catalytic reduction (SCR) catalyst.

7. The system of claim 6, wherein the thermal management mode remains active until the inlet temperature of the selective catalytic reduction catalyst is greater than a second temperature threshold.

8. The system of claim 7, wherein the first temperature threshold is 100 degrees Celsius and the second temperature threshold is 120 degrees Celsius.

9. The system of claim 1, wherein the transient response mode remains active until the lambda amount is greater than a second lambda threshold that is more than the first lambda threshold.

10. The system of claim 9, wherein the first lambda threshold is 1.6 and the second lambda threshold is 1.8.

11. The system of claim 1, further comprising the internal combustion engine, the internal combustion engine including: a plurality of cylinders for receiving an intake air flow and fuel; a plurality of spark plugs associated with respective ones of the plurality of cylinders; and a turbocharger that compresses the intake air flow using exhaust produced by combustion in the plurality of cylinders.Atty Docket No CMI002-00180 / 24-0031 -SRC12. A method for controlling combustion in an internal combustion engine, the method comprising: determining a post injection fueling condition is present for the internal combustion engine in response to a lambda amount during operation of the internal combustion engine; in response to the post injection fueling condition, activating either a transient response mode in response to the lambda amount being less than a first lambda threshold or activating a thermal management mode in response to the lambda amount being less than the first lambda threshold and an aftertreatment temperature being less than a first temperature threshold associated with a desired NOx conversion efficiency; selecting a post injection fuel amount from a transient response fueling table or from a thermal management fueling table associated depending on whether the transient response mode or the thermal management mode is activated; and injecting a base injection fuel amount and the post injection fuel amount after injecting the base injection fuel amount into a combustion chamber of the internal combustion engine during a combustion cycle of the internal combustion engine.

13. The method of claim 12, further comprising determining a base spark timing to combust the base injection fuel amount and a post spark timing to ignite the post injection fuel amount.

14. The method of claim 12, wherein the base injection fuel amount is an amount of fuel injected into the combustion chamber in the absence of the post injection fueling condition.

15. The method of claim 12, wherein the post injection fueling condition is present in response to a transient operating condition of the internal combustion engine.

16. The method of claim 12, wherein the aftertreatment temperature is an inlet temperature of a selective catalytic reduction (SCR) catalyst.

17. The method of claim 16, wherein the thermal management mode remains active until the inlet temperature of the selective catalytic reduction catalyst is greater than a second temperature threshold.Atty Docket No CMI002-00180 / 24-0031 -SRC18. The method of claim 17, wherein the first temperature threshold is 100 degrees Celsius and the second temperature threshold is 120 degrees Celsius.

19. The method of claim 12, wherein the transient response mode remains active until the lambda amount is greater than a second lambda threshold that is more than the first lambda threshold.

20. The method of claim 19, wherein the first lambda threshold is 1.6 and the second lambda threshold is 1.8.

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