Abstract: A method for a hydrogen fueled internal combustion engine to reduce backfiring, pre-ignition, and/or backflash, the engine also including a combustion chamber, an intake manifold, an exhaust manifold, at least one intake valve, at least one exhaust valve, a hydrogen injector, a compression device, and a variable valve timing system coupled to the intake valves. The method comprises compressing air using the compression device; injecting hydrogen and mixing at least said hydrogen with air discharged from the compression device; and opening the intake valve to induct at least air into the combustion chamber, wherein the intake valve opening time varies with an operating condition.

Abstract: A method for operating a fueling system in a vehicle having an engine capable of burning gaseous fuel supplied from at least a first and second source to a direct fuel injector of the engine, the first source having a higher source pressure than the second source, the method comprises supplying gaseous fuel to the direct injector from at least the first source during a first engine demand; and supplying gaseous fuel to the direct injector from at least the second source during a second engine demand less than said first engine demand.

Abstract: A method is provided for an engine capable of burning gaseous fuel, the engine also including a combustion chamber, a fuel supply system with at least one fuel tank, at least one intake valve, and at least one exhaust valve, an injector to directly inject gaseous fuel into the combustion chamber, and an exhaust oxygen sensor. The method comprises directly injecting fuel from the injector into the chamber at a variable supply pressure which decreases as fuel tank pressure decreases; and adjusting at least one of an injection time and duration based at least on said variable pressure and information from the exhaust oxygen sensor.

Abstract: A method for operating a fueling system in a vehicle having an engine capable of burning gaseous fuel supplied from at least a first and second source to a direct fuel injector of the engine, the first source having a higher source pressure than the second source, the method comprises supplying gaseous fuel to the direct injector from at least the first source during a first engine demand; and supplying gaseous fuel to the direct injector from at least the second source during a second engine demand less than said first engine demand.

Abstract: A method is provided for an engine capable of burning gaseous fuel, the engine also including a combustion chamber, a fuel supply system with at least one fuel tank, at least one intake valve, and at least one exhaust valve, an injector to directly inject gaseous fuel into the combustion chamber, and an exhaust oxygen sensor. The method comprises directly injecting fuel from the injector into the chamber at a variable supply pressure which decreases as fuel tank pressure decreases; and adjusting at least one of an injection time and duration based at least on said variable pressure and information from the exhaust oxygen sensor.

Abstract: An intake and exhaust system for a dual mode HCCI engine, which provides superior intake temperature control and homogeneity for engine operation in SI and HCCI modes, as well as during transition between SI and HCCI modes and vice-versa. The system includes adjusted intake cam movement event lengths for intake valve operation at specified modes of operation. The system further includes at least one cam profile switching device operatively connected to intake and exhaust valves in an engine for controlling event length, maximum lift, and valve opening/closing timings for the intake and exhaust valves. The system yet further includes a bifurcated intake system and camless valve actuators for controlling intake valves for facilitating operation in SI or HCCI modes, as well as transition between SI and HCCI modes and vice-versa.

Abstract: A method for a hydrogen fueled internal combustion engine to reduce backfiring, pre-ignition, and/or backflash, the engine also including a combustion chamber, an intake manifold, an exhaust manifold, at least one intake valve, at least one exhaust valve, a hydrogen injector, a compression device, and a variable valve timing system coupled to the intake valves. The method comprises compressing air using the compression device; injecting hydrogen and mixing at least said hydrogen with air discharged from the compression device; and opening the intake valve to induct at least air into the combustion chamber, wherein the intake valve opening time varies with an operating condition.

Abstract: A method for an engine capable of burning gaseous fuel, the engine also including a combustion chamber, at least one intake valve, and at least one exhaust valve, an injector to directly inject pressurized gaseous fuel into the combustion chamber, and a variable valve timing system coupled to the intake valves and exhaust valves, the method comprising closing the exhaust valve before top dead center of piston position to increase combustion chamber pressure achieved at top dead center and to trap exhaust gas in the cylinder; and starting injection of a gaseous fuel directly into the combustion chamber after the exhaust valve is closed and before the intake valve is opened.

Abstract: An intake and exhaust system for a dual mode HCCI engine, which provides superior intake temperature control and homogeneity for engine operation in SI and HCCI modes, as well as during transition between SI and HCCI modes and vice-versa. The system includes adjusted intake cam movement event lengths for intake valve operation at specified modes of operation. The system further includes at least one cam profile switching device operatively connected to intake and exhaust valves in an engine for controlling event length, maximum lift, and valve opening/closing timings for the intake and exhaust valves. The system yet further includes a bifurcated intake system and camless valve actuators for controlling intake valves for facilitating operation in SI or HCCI modes, as well as transition between SI and HCCI modes and vice-versa.

Abstract: An intake and exhaust system for a dual mode HCCI engine, which provides superior intake temperature control and homogeneity for engine operation in SI and HCCI modes, as well as during transition between SI and HCCI modes and vice-versa. The system includes adjusted intake cam movement event lengths for intake valve operation at specified modes of operation. The system further includes at least one cam profile switching device operatively connected to intake and exhaust valves in an engine for controlling event length, maximum lift, and valve opening/closing timings for the intake and exhaust valves. The system yet further includes a bifurcated intake system and camless valve actuators for controlling intake valves for facilitating operation in SI or HCCI modes, as well as transition between SI and HCCI modes and vice-versa.