Fuel injector

摘要

A method and apparatus is disclosed for ejecting material. The ejected material is ejected as liquid and liquid vapor via an explosive process which can provide a very fast ejection as well as an ejection which has a large throw. The apparatus can be used to eject fuel for a fuel injector.

主权项

1. Apparatus for injecting fuel into a combustion zone, comprising:
an ejection chamber to hold a portion of a liquid fuel; an inlet valve arranged to selectively open to transfer liquid fuel into the ejection chamber and then to selectively close to seal the portion of the liquid fuel in the ejection chamber; an exit valve arranged to selectively open to eject fuel from said ejection chamber through the exit valve in a vapor explosion process, then through a neck region when a parameter associated with said ejection chamber satisfies a predetermined condition such that opening of the exit valve causes liquid fuel in the ejection chamber to boil rapidly within the ejection chamber, the neck region being narrower in cross-sectional diameter than the ejection chamber; at least one pressure or temperature sensor that generates one or more signals for determining pressure in the ejection chamber; and an electronic controller for electronically controlling the inlet valve and the exit valve to selectively open and close based on the pressure in the ejection chamber determined from the one or more signals received from the at least one pressure or temperature sensor; wherein liquid fuel and/or liquid vapor are ejected from the ejection chamber into the combustion zone via the exit valve thereby injecting fuel into the combustion zone, and wherein said exit valve is arranged to open when a temperature of the liquid fuel in the ejection chamber is above a boiling point temperature associated with the liquid fuel at a downstream position from the exit valve, and wherein the parameter is the temperature of the liquid fuel in the ejection chamber and the predetermined condition is the temperature of the liquid fuel being above said boiling point temperature.