Methods and systems are provided for a fuel injector. In one example, a system may include forming an annular venturi passage between an outlet surface of the fuel injector and a nozzle. The nozzle may further comprise one or more air entraining features that may work in concert with the annular venturi passage to promote air-fuel mixing.

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.

Methods and systems are provided for a fuel injector. In one example, a system may include forming an annular venturi passage between an outlet surface of the fuel injector and a nozzle. The nozzle may further comprise one or more air entraining features that may work in concert with the annular venturi passage to promote air-fuel mixing.

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.

Systems are provided for cooling combustion chamber gasses and increasing an amount of air entrained in an injected fuel spray. In one example, a cooling passage may be included in an internal combustion engine, the cooling passage positioned exterior to a cylinder bore of the engine and coupled to the cylinder bore at a first opening and a second opening. The cooling passage may receive gasses from the cylinder bore via the first opening, and may cool the gasses as they travel through the cooling passage before returning the gasses to the cylinder bore via the second opening.

Systems are provided for cooling combustion chamber gasses and increasing an amount of air entrained in an injected fuel spray. In one example, a cooling passage may be included in an internal combustion engine, the cooling passage positioned exterior to a cylinder bore of the engine and coupled to the cylinder bore at a first opening and a second opening. The cooling passage may receive gasses from the cylinder bore via the first opening, and may cool the gasses as they travel through the cooling passage before returning the gasses to the cylinder bore via the second opening.

A ducted combustion system includes a combustion chamber and a fuel injector in fluid connection with the combustion chamber, which includes an orifice opening from an injector tip of the fuel injector, the orifice injecting fuel into the combustion chamber as a fuel jet, the fuel jet flowing, within the combustion chamber, in a fuel flow direction. The system includes at least one duct disposed within the combustion chamber, the at least one duct being disposed such that the fuel jet, at least partially, enters one of the at least one ducts upon being injected into the combustion chamber. The at least one duct may be configured for having a flow field air stream within the duct, prior to entrance of the fuel jet, the flow field air stream having a flow direction that is substantially similar to the fuel flow direction.

Systems are provided for cooling combustion chamber gasses and increasing an amount of air entrained in an injected fuel spray. In one example, a cooling passage may be included in an internal combustion engine, the cooling passage positioned exterior to a cylinder bore of the engine and coupled to the cylinder bore at a first opening and a second opening. The cooling passage may receive gasses from the cylinder bore via the first opening, and may cool the gasses as they travel through the cooling passage before returning the gasses to the cylinder bore via the second opening.