A fuel supply valve for a slurry fuel injector valve, the fuel supply valve comprising: a fuel inlet for fluid communication with a slurry fuel reservoir; a fuel outlet for fluid communication with a nozzle of the fuel injector valve; a pump chamber port for fluid communication with a pump chamber of the fuel injector valve; and a valve gate moveable between a first position, at which the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port, and a second position, at which the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port; wherein the valve gate is operable with a valve actuation liquid from an engine.

Disclosed is a slurry fuel injector valve, comprising: a fuel outlet valve through which slurry fuel is able to exit the slurry fuel injector valve towards a combustion chamber of an engine; a pump cavity; a pump element that divides the pump cavity into a pump chamber and an actuation chamber; a fuel conduit through which slurry fuel is flowable from the pump chamber to the fuel outlet valve; and an actuation fluid conduit through which actuation fluid is flowable from the actuation chamber to the fuel outlet valve.

An injector includes a housing including a fluid passage extending from an inlet of the housing to an outlet end of the housing. An actuator is mounted within the housing. A pintle extends along a longitudinal axis from an actuator end to a pintle head. The actuator end of the pintle is operatively connected to the actuator for actuation along the longitudinal axis. A tip member is mounted to the outlet end of the housing. The tip member includes an outlet orifice and a pintle seat. In a seated position of the pintle, the pintle head blocks flow to the outlet orifice. In an open position of the pintle, the pintle head allows flow. The pintle head includes a swirl passage therein, wherein the swirl passage is angled tangential relative to the longitudinal axis to induce swirl on flow passing between the pintle head and the pintle seat.

Fuel flows from first and second fuel guide channels into the swirl chamber and is guided to the nozzle hole while swirling in the swirl chamber in the identical direction. The nozzle hole is divided into an inlet portion near a fuel-inflow end and an outlet portion near a fuel-outflow end. The outlet portion has a flow passage cross-sectional area gradually increasing towards a fuel outflow-side opening end, and includes a curved surface formed by smoothly connecting an inner surface of the nozzle holes at an upstream end side in a fuel flow direction to an inner surface of the nozzle holes at the portion near the fuel-inflow end so as to smoothly and gradually increase the flow passage cross-sectional area. The curved surface ensures further thin film-like flow by expanding a flow of the fuel in the nozzle holes by the Coanda effect.

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.

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 supply valve for a slurry fuel injector valve, the fuel supply valve comprising: a fuel inlet for fluid communication with a slurry fuel reservoir; a fuel outlet for fluid communication with a nozzle of the fuel injector valve; a pump chamber port for fluid communication with a pump chamber of the fuel injector valve; and a valve gate moveable between a first position, at which the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port, and a second position, at which the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port; wherein the valve gate is operable with a valve actuation liquid from an engine.

Disclosed is a slurry fuel injector valve, comprising: a fuel outlet valve through which slurry fuel is able to exit the slurry fuel injector valve towards a combustion chamber of an engine; a pump cavity; a pump element that divides the pump cavity into a pump chamber and an actuation chamber; a fuel conduit through which slurry fuel is flowable from the pump chamber to the fuel outlet valve; and an actuation fluid conduit through which actuation fluid is flowable from the actuation chamber to the fuel outlet valve.

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.

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.