Abstract: A compression ignition internal combustion engine system includes an engine and an exhaust system with an upstream exhaust conduit, a downstream exhaust conduit, and an exhaust placement mechanism for mixing exhaust with fuel and air within engine cylinders. The upstream exhaust conduit has a raw exhaust inlet, a raw exhaust outlet, and a diesel exhaust fluid (DEF) inlet between the raw exhaust inlet and the raw exhaust outlet. The downstream exhaust conduit includes a bare particulate filter and a selective catalytic reduction (SCR) device. Related methodology including operating the engine in a startup mode, and in a running mode once the SCR device is warmed, is also disclosed.

Abstract: A system is disclosed that may include a gas recirculation passageway configured to recirculate gas exiting an engine to an intake of the engine prior to the gas reaching an aftertreatment system associated with the engine. The system may include a valve configured to control a gas recirculation of the gas recirculation passageway. The system may include a controller configured to cause, during a compression braking procedure for the engine, actuation of the valve to produce the gas recirculation when the aftertreatment system is performing an operation that is temperature-dependent.

Abstract: A compression ignition internal combustion engine system includes an engine and an exhaust system with an upstream exhaust conduit, a downstream exhaust conduit, and an exhaust placement mechanism for mixing exhaust with fuel and air within engine cylinders. The upstream exhaust conduit has a raw exhaust inlet, a raw exhaust outlet, and a diesel exhaust fluid (DEF) inlet between the raw exhaust inlet and the raw exhaust outlet. The downstream exhaust conduit includes a bare particulate filter and a selective catalytic reduction (SCR) device. Related methodology including operating the engine in a startup mode, and in a running mode once the SCR device is warmed, is also disclosed.

Abstract: A fuel injector includes an injector body, and a plunger movable within a plunger cavity in the injector body. The fuel injector also includes a spill valve positioned at least partially within a main fuel passage, a fill passage forming a fluid connection between the plunger cavity and the main fuel passage, and a cross passage forming a second fluid connection between the plunger cavity and the main fuel passage. The fuel injector also includes a metering edge within the plunger cavity and positioned such that the plunger passes the metering edge during pumping to the plunger for valvetrain noise suppression. A metering slot may be formed in the injector body or the plunger.

Abstract: A fuel injector includes an injector body, and a plunger movable within a plunger cavity in the injector body. The fuel injector also includes a spill valve positioned at least partially within a main fuel passage, a fill passage forming a fluid connection between the plunger cavity and the main fuel passage, and a cross passage forming a second fluid connection between the plunger cavity and the main fuel passage. The fuel injector also includes a metering edge within the plunger cavity and positioned such that the plunger passes the metering edge during pumping to the plunger for valvetrain noise suppression. A metering slot may be formed in the injector body or the plunger.

Abstract: A power system is provided having a first power source including at least one engine configured to combust a first air/fuel mixture and produce a first exhaust stream. The system also has a first exhaust passageway fluidly connected to the first power source and configured to receive the first exhaust stream. In addition, the system has a second power source including at least one engine configured to combust a second fuel/air mixture and produce a second exhaust stream. Furthermore, the system has a second exhaust passageway fluidly connected to the second power source and configured to receive the second exhaust stream.

Abstract: An exhaust treatment system is provided. The system may include a particulate trap configured to remove one or more types of particulate matter from an exhaust flow of an engine. The system may also include a catalyst configured to chemically alter at least one component of the exhaust flow. Further, the system may include an exhaust conduit configured to direct the exhaust flow from the engine to the particulate trap and the catalyst. In addition, the exhaust treatment system may include a heating system configured to maintain the temperature of the catalyst above a first predetermined temperature. The heating system may also be configured to periodically raise the temperature of the particulate trap above a higher, second predetermined temperature to thereby effectuate a regeneration of the particulate trap by oxidizing particulate matter accumulated in the particulate trap.

Abstract: A method of controlling engine NOx production is provided. The method may include determining a desired amount of NOx production for at least one engine cylinder at a first time and determining at least one engine operating parameter to produce the desired amount of NOx using a feed-forward neural network.

Abstract: A first aspect of the present disclosure includes a power source for use with selective catalytic reduction systems for exhaust-gas purification. The power source may comprise a first cylinder group with a first air-intake passage and a first exhaust passage, and a second cylinder group with a second air-intake passage and a second exhaust passage. The power source may further include a first forced-induction system in fluid communication with the first air-intake passage, and a second forced-induction system in fluid communication with the second air-intake passage. A catalyst may be disposed downstream of the fuel-supply device to convert at least a portion of the exhaust stream in the first exhaust passage into ammonia.

Abstract: A method of operating an internal combustion engine may include selectively operating the engine in a first mode of operation, wherein fuel may be injected into compressed fluid to create a substantially heterogeneous mixture of fuel and compressed fluid, and fuel may be ignited by the heat of the compressed fluid. The method may also include selectively operating the engine in a second mode of operation, wherein fuel is injected into gas to create a substantially homogeneous mixture of gas and fuel, the substantially homogeneous mixture is compressed, and fuel is ignited by the heat of the compressed gas. The method may further include determining whether to operate the engine in the first or second mode according to engine conditions.

Abstract: Often NOx selective catalysts that use ammonia to reduce NOx within exhaust to a harmless gas require on-board storage of ammonia which can be hazardous and inconvenient. In order to generate ammonia in exhaust, the present disclosure increases a NOx concentration in exhaust from at least one combustion chamber, at least in part, by injecting fuel in a predetermined increased NOx generation sequence that includes a first injection during non-auto ignition conditions and a second injection during auto ignition conditions. At least a portion of the NOx is converted to ammonia by passing at least a portion of the exhaust with the increased NOx concentration over an ammonia-producing catalyst.

Abstract: An engine system includes first and second combustion chamber groups that supply exhaust to respective first and second exhaust passages. NOx in the exhaust of the first combustion group is converted to ammonia, such as by enriching the exhaust with fuel and then passing the mixture over an appropriate catalyst. Particles are trapped and continuously oxidized through appropriate placement of one or more particle traps coated with an appropriate oxidizing catalyst. NOx in the second passage from the second combustion group is combined with ammonia produced in the first passage and converted to nitrogen and water in a merged passage before being vented to atmosphere. This conversion is accomplished by passing the merged exhaust over an appropriate selective catalytic reduction catalyst.

Abstract: Engines that include different combustion strategies for different cylinders may create a power imbalance resulting in undesirable engine vibrations. The engine system of the present disclosure includes a first engine that is operable to produce a high NOx concentration exhaust and a second engine that is operable to produce a low NOx concentration exhaust. The first engine is fluidly connected to a first section of an exhaust passage and the second engine is fluidly connected to a second section of the exhaust passage. The exhaust from the first engine and the exhaust from the second engine are merged in a merged section of the exhaust passage downstream from both the first and second sections of the exhaust passages. The high NOx concentration exhaust may be converted to ammonia for reacting with the low NOx concentration exhaust to arrive at very low NOx concentration from the merged exhaust.

Abstract: In certain engine systems, there may be a need, such as exhaust purification, to operate two power-producing portions of the engine system in different manners. The engine system of the present disclosure includes at least one engine that includes a first power-producing portion and a second power-producing portion. At least one electronic control module includes a high NOx generation algorithm in communication with the first power-producing portion and a low NOx generation algorithm in communication with the second power-producing portion. The high NOx generation algorithm is operable to signal at least one fuel injector within the first power-producing portion to inject fuel into at least one combustion chamber in a predetermined high NOx generation sequence that includes an injection during non-auto ignition conditions.

Abstract: A method of ammonia production for a selective catalytic reduction system is provided. The method includes producing an exhaust gas stream within a cylinder group, wherein the first exhaust gas stream includes NOx. The exhaust gas stream may be supplied to an exhaust passage and cooled to a predetermined temperature range, and at least a portion of the NOx within the exhaust gas stream may be converted into ammonia.

Abstract: A power source is provided for use with selective catalytic reduction systems for exhaust-gas purification. The power source has a first cylinder group fluidly connected to a first air-intake passage and a first exhaust passage, wherein the first air-intake passage is configured to provide air at a first set of characteristics. The power source also has a second cylinder group fluidly connected to a second air-intake passage and a second exhaust passage, wherein the second air-intake passage is configured to provide air at a second set of characteristics different from the first set of characteristics. An ammonia-producing catalyst may be disposed within the first exhaust passage and configured to convert at least a portion of a fluid in the first exhaust passage into ammonia.

Abstract: Particularly in an engine that has been inactive for a substantial period of time at a cold temperature, fluid forces acting on moving members, such as electronically-activated fluid control valves, may be significant until the engine warms up. A way to reduce the fluid forces and their detrimental effects is to reduce the volume of fluid which are creating the fluid forces, including venting all or some of this fluid to drain. Additionally, fluid that gathers can be drained away. In order to accomplish such venting, the present disclosure includes a fluid control valve having a body with at least one fluid passage connected to a bore, a movable member in the bore, an actuator connected to the movable member to move the movable member, and at least one vent passage opening into the bore between the fluid passage and the actuator. The disclosure may include additional drain passages to drain away gathered fluid from actuating components.

Abstract: A method of removing sulfur from a filter system of an engine includes continuously passing an exhaust flow through a desulfation leg of the filter system during desulfation. The method also includes sensing at least one characteristic of the exhaust flow and modifying a flow rate of the exhaust flow during desulfation in response to the sensing.

Abstract: A power source is provided for use with selective catalytic reduction systems for exhaust-gas purification. The power source includes a first cylinder group with a first air-intake passage and a first exhaust passage, and a second cylinder group with a second air-intake passage and a second exhaust passage. The second air-intake passage is fluidly isolated from the first air-intake passage. A fuel-supply device may be configured to supply fuel into the first exhaust passage, and a catalyst may be disposed downstream of the fuel-supply device to convert at least a portion of the exhaust stream in the first exhaust passage into ammonia.

Abstract: An internal combustion engine has at least one combustion chamber and a piston slidably disposed within the at least one combustion chamber. The piston is configured to reciprocate between a top-dead-center position and a bottom-dead-center position. The internal combustion engine also has an air supply in selective fluid communication with the at least one combustion chamber and a fuel supply in selective fluid communication with the at least one combustion chamber. The internal combustion engine further has a supply of non-combustible gas and at least one injector in fluid communication with the at least one combustion chamber and the supply of non-combustible gas. The at least one injector is configured to inject non-combustible gas from the supply into the at least one combustion chamber.