Abstract: A gas engine is disclosed. The gas engine may include a combustion cylinder. The combustion cylinder may include an intake with an intake valve. The combustion cylinder may include an exhaust with an exhaust valve. The gas engine may include a gas admission valve assembly coupled to the intake. The gas admission assembly may include a trimmable electro-hydraulically actuatable gas admission valve to control a gas flow into the intake.

Abstract: An engine control system comprises a balancing arrangement together with a knock mitigation controller configured to implement a knock mitigation procedure wherein an offset input value (VI) is applied to the balancing algorithm. The offset input value (VI) may cause the balancing algorithm to adjust the control output (O1) for the respective one of the combustion chambers to progressively vary the fuel supply or ignition timing for the affected cylinder to mitigate the knock condition. Alternatively, the controller may generate an offset output value (VO) to more rapidly vary the fuel supply or ignition timing, with the offset input value (VI) being selected for example to compensate for the resulting change in the control input (I1) from the cylinder to the balancing algorithm, or to provide additional, more gradual adjustment to further mitigate the knock condition.

Abstract: A control system for controlling pilot fuel injection in a dual fuel engine is disclosed. The control system may determine, using measurements from one or more sensors, one or more combustion parameters associated with the dual fuel engine during operation of the dual fuel engine. The control system may determine an estimated nitrogen oxides (NOx) emissions level based on the one or more combustion parameters, and may determine a NOx error based on a comparison between the estimated NOx emissions level and a desired NOx emissions level. The control system may control a quantity of pilot fuel injected into the dual fuel engine based on the NOx error.

Abstract: A control system for controlling pilot fuel injection in a dual fuel engine is disclosed. The control system may determine, using measurements from one or more sensors, one or more combustion parameters associated with the dual fuel engine during operation of the dual fuel engine. The control system may determine an estimated nitrogen oxides (NOx) emissions level based on the one or more combustion parameters, and may determine a NOx error based on a comparison between the estimated NOx emissions level and a desired NOx emissions level. The control system may control a quantity of pilot fuel injected into the dual fuel engine based on the NOx error.

Abstract: A gas engine is disclosed. The gas engine may include a combustion cylinder. The combustion cylinder may include an intake with an intake valve. The combustion cylinder may include an exhaust with an exhaust valve. The gas engine may include a gas admission valve assembly coupled to the intake. The gas admission assembly may include a trimmable electro-hydraulically actuatable gas admission valve to control a gas flow into the intake.

Abstract: An engine control system comprises a balancing arrangement together with a knock mitigation controller configured to implement a knock mitigation procedure wherein an offset input value (VI) is applied to the balancing algorithm. The offset input value (VI) may cause the balancing algorithm to adjust the control output (O1) for the respective one of the combustion chambers to progressively vary the fuel supply or ignition timing for the affected cylinder to mitigate the knock condition. Alternatively, the controller may generate an offset output value (VO) to more rapidly vary the fuel supply or ignition timing, with the offset input value (VI) being selected for example to compensate for the resulting change in the control input (I1) from the cylinder to the balancing algorithm, or to provide additional, more gradual adjustment to further mitigate the knock condition.

Abstract: Apparatus and methods for injecting gaseous fuel into a compression ignition engine are disclosed. A gaseous fuel injector includes a pintle valve and an intensifier. The pintle valve includes a pintle body defining a pintle bore therethrough, a first sealing surface disposed on a distal end of the pintle body, and a pintle disposed within the pintle bore. The pintle includes a shaft, a radially flared portion, and a second sealing surface disposed on a proximal face of the radially flared portion, such that the first sealing surface faces the second sealing surface. The intensifier includes an intensifier body defining a fuel pump chamber therein, the fuel pump chamber being fluidly coupled to a gaseous fuel supply and the pintle bore, a plunger having a distal end disposed in the fuel pump chamber, and an intensifier piston disposed on a proximal end of the plunger.

Abstract: Apparatus and methods for injecting gaseous fuel into a compression ignition engine are disclosed. A gaseous fuel injector includes a pintle valve and an intensifier. The pintle valve includes a pintle body defining a pintle bore therethrough, a first sealing surface disposed on a distal end of the pintle body, and a pintle disposed within the pintle bore. The pintle includes a shaft, a radially flared portion, and a second sealing surface disposed on a proximal face of the radially flared portion, such that the first sealing surface faces the second sealing surface. The intensifier includes an intensifier body defining a fuel pump chamber therein, the fuel pump chamber being fluidly coupled to a gaseous fuel supply and the pintle bore, a plunger having a distal end disposed in the fuel pump chamber, and an intensifier piston disposed on a proximal end of the plunger.

Abstract: A gaseous fuel internal combustion engine includes an engine housing defining at least one cylinder, and an intake housing defining an intake passage fluidly connecting with the at least one cylinder. The engine includes a gaseous fuel delivery mechanism coupled with the engine housing and a distributed ignition promoting mechanism having a bead presentation device extending into the intake passage and configured to present a liquid bead of distributed ignition promoting material therein such as engine lubricating oil. During operation, gases passing through the intake passage dislodge the liquid bead from the bead presentation device and carry the distributed ignition promoting material into the cylinder for distributively igniting therein a mixture containing a gaseous fuel, air and the distributed ignition promoting material.

Abstract: A gaseous fuel internal combustion engine includes an engine housing defining at least one cylinder, and an intake housing defining an intake passage fluidly connecting with the at least one cylinder. The engine includes a gaseous fuel delivery mechanism coupled with the engine housing and a distributed ignition promoting mechanism having a bead presentation device extending into the intake passage and configured to present a liquid bead of distributed ignition promoting material therein such as engine lubricating oil. During operation, gases passing through the intake passage dislodge the liquid bead from the bead presentation device and carry the distributed ignition promoting material into the cylinder for distributively igniting therein a mixture containing a gaseous fuel, air and the distributed ignition promoting material.

Abstract: A method of operating an engine is provided. The engine may have a housing with one or more combustion chambers, including a first combustion chamber. The engine may also have a piston in fluid communication with the first combustion chamber. The method may include combusting fuel in the first combustion chamber, thereby producing combustion gas that expands and drives the piston during a first combustion-gas-expansion stroke of the piston. The method may also include compressing at least part of the combustion gas in the first combustion chamber during a compression stroke of the piston. Additionally, the method may include, between commencement of the first combustion-gas-expansion stroke and completion of the compression stroke, releasing part of the combustion gas from the first combustion chamber.

Abstract: A multiple spark pattern internal combustion initiation device includes a body defining a prechamber and a plurality of orifices from the prechamber. The device includes at least two electrical circuits which each form a spark gap with an electrical ground inside the prechamber, operable to create a plurality of different spark patterns. The device may be part of an internal combustion engine which includes a housing with a combustion chamber connected to the prechamber, and means for supplying a lean gaseous fuel mixture into the combustion chamber.

Abstract: A multiple spark pattern internal combustion initiation device includes a body defining a prechamber and a plurality of orifices from the prechamber. The device includes at least two electrical circuits which each form a spark gap with an electrical ground inside the prechamber, operable to create a plurality of different spark patterns. The device may be part of an internal combustion engine which includes a housing with a combustion chamber connected to the prechamber, and means for supplying a lean gaseous fuel mixture into the combustion chamber.

Abstract: An internal combustion engine having a compression ignition initiation device is provided. The compression ignition initiation device includes a body defining a chamber and an outlet from the chamber. The device further includes means, within the chamber, for generating a combustion initiating shock front from the outlet. A method is provided, including compressing a mixture of fuel and air in an internal combustion engine cylinder to a point less than a compression ignition threshold, and initiating ignition of the mixture by subjecting it to a shock front.

Abstract: An air induction system for an engine is disclosed. The air induction system has a compressor operable to compress air directed into the engine, a bypass valve, and a throttle valve. The bypass valve may be disposed between the compressor and the engine and may have a valve element movable to selectively divert a portion of the compressed air away from the engine in response to a desired air-to-fuel ratio of the engine. The throttle valve may be disposed between the bypass valve and the engine and may have a valve element movable to selectively restrict the flow of compressed air into the engine in response to a desired air-to-fuel ratio of the engine. The movements of the valve elements of the bypass and throttle valves may be substantially sequential.

Abstract: An internal combustion engine has at least one combustion chamber and a piston configured to reciprocate within the at least one combustion chamber between a top-dead-center position and a bottom-dead-center position. The internal combustion engine also has a pre-combustion chamber, an air induction system, a fuel system, a spark plug at least partially disposed within the pre-combustion chamber. The air induction system is configured to direct air into the at least one combustion chamber. The fuel system is configured to direct gasoline into the at least one combustion chamber. The spark plug is configured to selectively ignite a mixture of the air and gasoline. The internal combustion engine also has an exhaust system configured to direct exhaust from the at least one combustion chamber and an exhaust gas recirculation system configured to selectively redirect at least a portion of the exhaust from the exhaust system back to the air induction system.

Abstract: An internal combustion engine and method of operating an engine is provided. The engine comprises a piston cylinder formed within an engine block, an engine head secured to the engine block, a primary piston configured to slide within the piston cylinder, a main combustion chamber that is defined by the primary piston, piston cylinder, and engine head, a variable volume prechamber formed within the engine head and in fluid communication with the main combustion chamber, an ignition device configured to ignite a fuel within the prechamber, and a prechamber piston configured to translate within the prechamber. Translation of the prechamber piston within the prechamber varies the volume within the prechamber. The engine is characterized in that the prechamber comprises at least one orifice that provides fluid communication between the prechamber and the main combustion chamber.

Abstract: A method of operating an internal combustion engine is provided. The engine includes a main combustion chamber in fluid communication with a prechamber. The method comprises the step of varying the volume within the prechamber during a portion of a compression stroke of the main combustion chamber.

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.