Ejector and fuel cell system therewith

摘要

Provided are an ejector which is capable of linearly controlling an ejection flow rate relative to the amount of movement of a needle to enhance its overall applicability and a fuel cell system with this ejector. The ejector 24 includes a nozzle 46 for ejecting a fluid, a needle 48 disposed coaxial with the nozzle 46 and having a tip end portion 48 a which faces the nozzle 46 , and needle moving means 49 for causing the needle 48 to advance and retreat axially. The shape of the tip end portion 48 a of the needle 48 is set such that the opening area Y of the gap between the tip end portion 48 a of the needle 48 and the nozzle 46 and the amount Z of movement produced by the needle moving means 49 satisfy a proportional relationship.