Performance of Pressure-Exchange Ejector at Different Port Pressure

Abstract

Pressure-exchange ejector is a novel device which can transfer energy between fluids by pressure waves, so the pressure of each port is very important. A prototype was designed and the experiment system was set up. The performance of pressure-exchange ejector at different overall pressure ratio and outlet pressure was investigated. Results showed that the entrainment ratio of pressure-exchange ejector reduced with larger pM, while the overall isotropic efficiency tended to go up with increasing outlet pressure pM and then falled down. Higher efficiency could be obtained when the outlet pressure was close to the average pressure of the channel after a cycle. Besides, the efficiency of pressure-exchange ejector decreased as the overall pressure ratio increasing. The maximum efficiency was about 60% when pH/pL=1.5, while for pH/pL=2.0, the maximum efficiency reduced by 15%. However this value was also much higher than that of the steady flow ejector. The excellent performance makes pressure-exchange ejector a promising device for natural gas exploitation.