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.

A fuel distributor, for example that is usable as a fuel rail for mixture-compressing spark-ignition internal combustion engines, includes a main body, on which a plurality of high-pressure outlets are provided. The main body includes at least one dividing wall that at least largely separates an inflow region from a damping region within the main body. The main body is made up of at least two profiles that are joined to each other.

Method for reducing intake valve deposits in a spark ignition internal combustion engine which is fuelled with a gasoline fuel composition, wherein the method comprises introducing into the engine an aqueous based composition, wherein the aqueous based composition comprises (i) water, (ii) from 0 vol % to 40 vol % freezing point suppression agent, (iii) from 0 vol % to 10 vol % of surfactant, and (iv) an amine compound in a blending amount of from 0 ppmw to 1000 ppmw.

A secondary fluid is provided for use in an internal combustion engine that burns a primary fuel. The secondary fluid comprises about 15 vol % to about 30 vol % of alcohol; and about 0.0025 vol % to about 0.5 vol % of a lubricity enhancer which optionally is a castor oil. The secondary fluid is a thermodynamically stable microemulsion with water being the continuous phase.

An internal combustion engine includes a cylinder with a combustion chamber and a piston selectively changing the volume of the combustion chamber. The combustion chamber receives a mixture of air, hydrogen and a liquid fuel consisting essentially of water and a flammable, preferably non-fossil, substance. The contents of the combustion chamber are ignited generating power.

Methods and systems are provided for accurately determining the composition of a knock control fluid using sensors already present in the engine system. An intake or an exhaust oxygen sensor is used to estimate the water and the alcohol content of a knock control fluid that is direct injected into an engine cylinder responsive to an indication of abnormal combustion. A change in the pumping current of the oxygen sensor due to the water content of the knock control fluid is distinguished from a change in the pumping current of the oxygen sensor due to the alcohol content of the knock control fluid.

A method for controlling an engine system, may include a water injection operation of injecting water into an intake system of an engine through a water injector of a water injection system in a first operating condition of the engine in which water injection is required, a compressed air injection operation of injecting compressed air into the intake system through a purge circuit of the water injection system in a second operating condition of the engine in which compressed air injection is required, and a water injection stop operation of stopping the water injection of the water injection system in a third operating condition of the engine in which water injection stop is required.

What is proposed is an emulsifying system for an internal combustion engine, wherein the emulsifying system comprises an emulsifying device for producing a water-fuel emulsion and an injector for injecting the water-fuel emulsion in a combustion chamber, the emulsifying device being arranged within the injector. Also proposed is an emulsifying method for preparing a water-fuel emulsion for an internal combustion engine, wherein fuel is pressurized in a fuel pressure accumulator and water is pressurized in a water pressure accumulator and fed separately to an injector for injecting the fuel and water into an associated combustion chamber, and/or fuel and water are emulsified by means of an emulsifying device that is integrated into an injector.