Abstract
The present stury describes a new method to improve the performance of the ejector which can be employed for the hydrogen fuel cell system. A cone cylinder is inserted into a conventional ejector-diffuser system. Experiment is carried out to investigate the operation characteristics of the variable sonic and supersonic ejector system. For a wide range of the operation pressure ratios of the ejector system, the mass flow rate of suction flow is measured. The results obtained show that the present variable ejector system can control the suction flow rate at a fixed operation pressure ratio, and that the sonic ejector is considerably different from the spersonic ejector system. As the ejector throat area ration increases, the recirculation ration of suction flow increases for the sonic ejector, but it decreases for the supersonic ejector. The present variable ejector system can effectively control the suction mass flow rate.
