Abstract:
A system and method for the direct injection of a gaseous fuel into an internal combustion engine. The gaseous fuel injection system (10) delivers metered amounts of gaseous fuel directly into the combustion chamber of an engine. The injection system (10) is configured as a 'two-stage' system, comprising a gaseous fuel metering means (12) and a delivery injector (14). The metering means (12) is arranged coaxially with the delivery injector (14) such that gaseous fuel metered thereby can be received by the delivery injector (14) for subsequent delivery to the engine. A holding chamber (16) is arranged intermediate of the metering means (12) and delivery injector (14). Operation of the engine (30) and the injection system (10) is controlled by an engine control means comprising a suitably programmed electronic control unit. The injection system (10) is configured to promote operation of the metering means (12) with a sonic flow during the gaseous fuel metering event. For this purpose, a region downstream of the metering means (12) and within the injection system (10) is configured and sized to promote operation of the metering means (12) with a sonic flow during the gaseous fuel metering event. Specifically, the metering means (12) and the delivery injector (14) are arranged and/or configured to ensure sonic flow through the metering means (12) when it is opened and is metering gaseous fuel. The delivery injector (14) may also be arranged and/or configured so as to promote sonic flow throughout a gaseous fuel delivery event. Typically, the holding chamber (16) is configured to be of a sufficient volume to ensure sonic flow throughout the metering event.
Abstract:
A supplementary slurry fuel atomizer of this invention, when used on a piston internal combustion engine, equipped with a common rail fuel injection system, improves slurry atomization, following injection, by expansion of gases, previously dissolved in the water phase of the slurry. This gas expansion separates the several fuel particles in each slurry droplet formed first during fuel injection. The thusly separated fuel particles subsequently burn more rapidly and completely, due to this fuel particle separation improving air access to the fuel. Apparatus is described for dissolving atomizing gas into the water phase of the slurry, in a contactor chamber at a pressure greater than the pressure prevailing in the engine cylinder volume, at the time of slurry injection.
Abstract:
The present invention relates to a fuel injection arrangement for a diesel type engine configured to use carbonaceous aqueous slurry fuels. The fuel injection arrangement includes an injector nozzle for injecting fuel into a combustion chamber; a pump chamber housing a fuel pumping element for generating a pressurised fuel flow to the injector nozzle along an injection path between the pumping element and the injector nozzle; and a check valve connected to a fuel supply for regulating and supplying fuel to the injection path via a check valve outlet. A region immediately downstream of the check valve outlet defines an outlet region and the check valve is arranged to expose the outlet region to the pressurised fuel flow to facilitate flushing of the outlet region during fuel flow between the pumping element and the injector nozzle.
Abstract:
The present invention provides an improved fuel injection system and related method for controlling fuel heating and circulation in diesel type engines configured to use carbonaceous aqueous slurry fuels. The fuel injection system comprises: at least one fuel injector including an injector nozzle through which fuel is atomised and a fuel injector pump for pressurising fuel for supply to the injector nozzle; and a controlled bleed valve fluidly connected to each fuel injector and positioned to allow a controlled amount of carbonaceous aqueous slurry fuel to flow from the fuel injector.