Various methods and systems are provided for a method for a multi-pressure fueling system. In one example, the multi-pressure fueling system includes providing a first fuel delivery pressure enabling high pressure direct injection of a fuel at a first injector and a second fuel delivery pressure insufficient for high pressure direct injection, at a second injector, based on engine operation.

The invented system adds some petrol fuel to the vehicle engine which runs with natural gas (CNG or LPG). It causes a simultaneous combustion of petrol and natural gas (CNG or LPG). This action decreases depreciation of engine, increases power of the engine and reduces fuel consumption in natural gas vehicles. The above-mentioned system consists of an innovative petrol holder storage, an electronically circuit, a relay, a lever micro switch and a petrol fuel injector. Whenever the accelerator pedal is pressed more than a certain amount, the system will be activated and command to inject petrol collected in the storage into the air manifold.

A pump has a plurality of pumping elements, each being independently responsive to an actuation signal from a controller. The controller is programmed to maintain a desired pressure at the pump discharge, monitor the fluid pressure at the pump discharge, compare the fluid pressure with the desired fluid pressure to determine a pressure error, provide commands to sequentially actuate the pumping elements when the pressure error is within a threshold range, and provide commands to actuate more than one of the plurality of pumping elements simultaneously, such that more than one pumped amounts of fluid are delivered simultaneously at the pump discharge, when the pressure error droops outside of the threshold range.

A system for exchanging of different fuels that can be used for operation of an engine. The system includes a fuel exchange unit, a control and an exchange return conduit. The fuel exchange unit is configured to deliver a first fuel at pressure into the injections system given a switched-off engine, in order to replace a second fuel, which is located in the injection system, with the first fuel. A fuel delivery system includes a media converter which includes a deflectable element. The media converter is driven by a drive unit via the fluid by way of the fluid being able to be led at a varying pressure to the media transformer via a first feed conduit, and is configured to deliver the fuel via a pumping effect.

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 relates to fuel systems for diesel engines. In particular, the invention relates to a dual fuel supply system (10) for a diesel engine having an indirect-injection system (12). The invention extends to a diesel engine incorporating the dual fuel supply system (10) and to a vehicle that incorporates a diesel engine having the dual fuel supply system (10). The dual-fuel supply system (10) includes a mixed fuel supply system (17) that includes a first stage (14) having a diesel tank (42) and LPG tank (44), and as second stage (16) to supply the fuel mixture to the injection system (12). The dual-fuel supply system (10) also includes diesel supply system (80) for delivering diesel to the injection system (12). Moreover, the dual fuel system (10) is configured to permit selective change over between the diesel supply system (80) and the mixed fuel system (17) to supply the injection system (12) selectively with either diesel or liquid fuel mixture respectively.

A method for operating a common-rail fuel supply system of an internal combustion engine includes determining, dependent on an operating point of the engine, a set point rate of delivery of the high-pressure pumping device, and a set point pressure for the pressure storage system under high pressure, determining, dependent on a deviation between the set point pressure and an actual pressure in the pressure storage system, for a first part quantity of the throttle valves a closed-loop control portion for the position of the respective throttle valve, and activating the first part quantity of the throttle valves with the closed-loop control portion in addition to open-loop control for only the respective throttle valve of the first part quantity of the throttle valves. The, or each, throttle valve of a second part quantity of the throttle valves is exclusively activated with the open-loop control portion.

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.

The present invention relates to a gas tank arrangement (100) for an internal combustion engine (102), said gas tank arrangement (100) comprising a gas tank (104) for containing a combustible gas, and an additional gas tank (106) arranged in upstream fluid communication with said internal combustion engine (102), wherein the gas tank arrangement (100) further comprises a valve arrangement (108) positioned in fluid communication with the internal combustion engine (102), wherein the valve arrangement (108) is further arranged in upstream fluid communication with the gas tank (104) and the additional gas tank (106) for controllably direct combustible gas from the internal combustion engine (102) to either the gas tank (104) or the additional gas tank (106).

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.