An injector includes a nozzle body extending along a longitudinal axis and at least one spray hole extending through a portion of the nozzle body to output a fluid from the injector. The spray hole includes at least one groove. The groove is configured to facilitate efficient mixing of the fluid with air or other surrounding materials for enhanced performance of the injector and/or other components associated with the injector.

A needle for a jet device includes a needle body and a tapered part arranged at the end of the needle body, in which the needle body is circumferentially provided with supporting bodies, so that when the needle is assembled in a nozzle of the jet device, the outer surfaces of the supporting bodies are coordinated with an inner chamber of the nozzle to limit the position of the needle body and form fluid channels among the supporting bodies, thereby to effectively prevent the needle from deviating from the spout of the nozzle or from radially swinging.

A nozzle hole of a nozzle plate is connected to a fuel injection nozzle of a fuel injection unit through a swirl chamber and first and second fuel guide grooves opened to the swirl chamber. The swirl chamber is an oval recess provided with the nozzle orifice in its center. A first fuel guide groove is opened to one end side of a major axis of the oval recess, and a second fuel guide groove is opened to the other end side of the major axis of the oval recess. The first and second fuel guide grooves are formed such that the same amount of fuel flows to the swirl chamber. The same amount of fuel flowing from the first and second fuel guide grooves to the swirl chamber is guided to the nozzle orifice at the same time while revolving inside the swirl chamber in the same direction.

A nozzle needle for an injector for injecting fuel includes at least one guiding section with a recess and a guiding surface configured to rest against an inner surface of a nozzle body of the injector, the recess at least partially delimiting the guiding surface and being configured to allow a flow of fuel along the guiding section, and the guiding surface being guided about the longitudinal axis of the nozzle needle in a helical manner.

An injector is provided, comprising: a valve seat having a needle opening extending from an upper surface along a longitudinal axis and terminating at a seating surface configured to mate with a valve needle to control flow of fluid through the injector, and a nozzle plate. The valve seat further comprises a plurality of drillings and a corresponding plurality of swirl channels, each of the plurality of drillings being in flow communication with the needle opening and a swirl channel. Each of the swirl channels directs flow of fluid from one of the drillings toward the longitudinal axis into a central swirl chamber. The nozzle plate includes a substantially flat upper surface that engages the valve seat lower surface and includes an opening in flow communication with a metering orifice, the opening being aligned with the central swirl chamber when the nozzle plate is attached to the valve seat.

A fuel supply valve for a slurry fuel injector valve comprises a fuel inlet in fluid communication with a slurry fuel reservoir. A fuel outlet is in fluid communication with a nozzle of the fuel injector valve. A pump chamber port is in fluid communication with a pump chamber of the fuel injector valve. A valve gate is moveable between a first position wherein the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port and a second position wherein the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port. Wherein the valve gate is arranged to not substantially exert a force opposing a flow on the slurry fuel into the valve chamber when the valve gate moves between the second position and the first position and/or between the first position and the second position.

Disclosed is a valve needle for a needle valve of a slurry fuel injector valve, the valve needle comprising: a tip for abutting a needle valve seat of the needle valve; a sealing portion for location in a bore of the needle valve; and a fuel chamber portion between the tip and the sealing portion, wherein the fuel chamber portion is for location in a needle fuel chamber of the needle valve; wherein a surface of the sealing portion of the valve needle comprises at least one groove and wherein at least part of the or each groove extends in a direction that is non-perpendicular to an axial direction of the valve needle.

Methods and systems are provided for a fuel injector. In one example, a system may include an injection nozzle having a venturi shape with an upstream twisted fin arranged in a venturi inlet. The system may further include a downstream twisted fin arranged in a venturi outlet.

A fuel and gas mixing structure for an engine is provided. This mixing structure includes a body configured to be positioned between a fuel injector and a cylinder of an engine. The body defines an interior volume that is configured to receive gas from outside the body and to receive one or more streams of fuel from the fuel injector in the interior volume. The body also defines one or more mixture conduits configured to conduct plumes of the fuel and gas, while mixing, from the interior volume to one or more exit ports and therethrough to the cylinder.

A fluid injector assembly extending along a longitudinal axis comprising a housing, and an injector positioned within the housing, the injector comprising a injector body having an interior cavity, a plunger positioned within the interior cavity and comprising a plunger body, a fluid delivery passage along at least a portion of the plunger body, and a plunger tip positioned at a downstream end of the plunger body, the fluid delivery passage comprising a longitudinal passage and at least one internal swirl passage, and the internal swirl passage being angled relative to the longitudinal axis and extending from the longitudinal passage to an opening upstream of the plunger tip, and a nozzle positioned at a downstream end of the injector body and including at least one nozzle passage, fluid being delivered from an upstream end of the injector to the at least one nozzle passage through the fluid delivery passage.