A fuel system for an internal combustion piston engine includes a first fuel section and a second fuel section in which the first fuel section has a first inlet line connecting respective inlets of the injectors to a tank, and the second fuel section has a second inlet line connecting respective inlets of the injectors to a fuel tank. The second fuel section is arranged to inject the fuel into the combustion chambers for igniting the first fuel, in which first fuel section the inlet line extends from a high pressure pump to the respective injectors, and a fuel return line of the first fuel section extends from each of the injectors to the tank. The fuel return line has a pressure increasing means arranged to the fuel return line of the first fuel section between the injectors and the tank.

A fuel system for an internal combustion piston engine includes a first fuel section and a second fuel section in which the first fuel section has a first inlet line connecting respective inlets of the injectors to a tank, and the second fuel section has a second inlet line connecting respective inlets of the injectors to a fuel tank. The second fuel section is arranged to inject the fuel into the combustion chambers for igniting the first fuel, in which first fuel section the inlet line extends from a high pressure pump to the respective injectors, and a fuel return line of the first fuel section extends from each of the injectors to the tank. The fuel return line has a pressure increasing means arranged to the fuel return line of the first fuel section between the injectors and the tank.

The present invention provides systems, methods and apparatus to overcome limitations of liquid fuel engine combustion. Liquid fuel is mixed with superheated water which vaporizes, mixes with air and ignites within the injector nozzle. The injector nozzles then accelerate the mixture into the engine combustion chamber where unburned fuel vapor mixes and burns. Combustion begins the instant of injection and increases uniformly. Combustion pressure builds progressively. Combustion of fuel vapor is more ideal, and better controlled. As part of the system and apparatus, the present disclosure also includes a low-cost high-speed solenoid valve which produces shorter injection pulses. It also includes a high-speed, high-air-volume solenoid fuel valve. In addition, the present invention and its disclosure create tools to develop and optimize this new method of fuel vapor injection.

A fuel atomizer that includes a housing having a fuel inlet and at least one primary orifice positioned at the inlet, wherein the at least one orifice configured to disperse a stream of fuel into a plurality of fuel droplets. The plurality of fuel droplets contact a fuel impingement surface to break up the plurality of fuel droplets into a plurality of smaller secondary droplets and create a thin film of secondary droplets on the impingement surface. At least one pressurized air channel delivers an airflow into contact with the secondary droplets. The secondary droplets pass through a plurality of secondary outlet orifices to exit the housing. A size of the plurality of secondary droplets is reduced when passing out of the plurality of secondary orifices.

A fuel atomizer that includes a housing having a fuel inlet and at least one primary orifice positioned at the inlet, wherein the at least one orifice configured to disperse a stream of fuel into a plurality of fuel droplets. The plurality of fuel droplets contact a fuel impingement surface to break up the plurality of fuel droplets into a plurality of smaller secondary droplets and create a thin film of secondary droplets on the impingement surface. At least one pressurized air channel delivers an airflow into contact with the secondary droplets. The secondary droplets pass through a plurality of secondary outlet orifices to exit the housing. A size of the plurality of secondary droplets is reduced when passing out of the plurality of secondary orifices.

Systems and methods are provided for air and fuel delivery within a pre-chamber. In one example, an engine pre-combustion chamber comprises a first chamber portion centered along a first axis, and a second chamber portion joined to the first chamber portion and centered along a second axis arranged at an angle to the first axis. In this way, wall wetting may be decreased while favorable charge motion for robust ignition may be increased.

A dual fluid injection system which comprises a liquid fuel metering device, a fluid delivery device, and apparatus providing an interface therebetween. The interface conveys liquid fuel along a flow path from the metering device to a mixing zone for mixing with air from a pressurized supply to provide an air-fuel mixture for injection by the fluid delivery device into a combustion chamber of an internal combustion engine. The flow path may involve a directional change by way of a turn section. The flow path is sized such that liquid fuel is retained therein by virtue of capillary action, whereby a quantity of liquid fuel is retained after a delivery event such that the flow path remains substantially filled with liquid fuel in readiness for the next delivery event during operation of the engine.

A dual fluid injection system which comprises a liquid fuel metering device, a fluid delivery device, and apparatus providing an interface therebetween. The interface conveys liquid fuel along a flow path from the metering device to a mixing zone for mixing with air from a pressurized supply to provide an air-fuel mixture for injection by the fluid delivery device into a combustion chamber of an internal combustion engine. The flow path may involve a directional change by way of a turn section. The flow path is sized such that liquid fuel is retained therein by virtue of capillary action, whereby a quantity of liquid fuel is retained after a delivery event such that the flow path remains substantially filled with liquid fuel in readiness for the next delivery event during operation of the engine.

A method of controlling fuel delivery to an engine includes providing a fluid atomizer, a mechanically driven air compressor, a start up air source, and an air valve coupled between the mechanically driven air compressor and the start up air source, charging the start up air source, delivering compressed air from the start up air source to the fluid atomizer, providing an initial air/fluid mixture with the fluid atomizer, and operating the air valve to direct compressed air from the mechanically driven air compressor to the fluid atomizer.

A method of controlling fuel delivery to an engine includes providing a fluid atomizer, a mechanically driven air compressor, a start up air source, and an air valve coupled between the mechanically driven air compressor and the start up air source, charging the start up air source, delivering compressed air from the start up air source to the fluid atomizer, providing an initial air/fluid mixture with the fluid atomizer, and operating the air valve to direct compressed air from the mechanically driven air compressor to the fluid atomizer.