Influence of Operating Parameters on the Ejector Performance Based on CFD Simulation

doi:10.12068/j.issn.1005-3026.2019.11.014

Abstract

Abstract: The influences of the different operating parameters on flow characteristic of internal flow field and the ejector performance are discussed by CFD method. With the increase of the primary fluid pressure， the flow area of the secondary fluid pressure decreases at the choking position， however， the Mach number and the entrainment ratio both gradually increased， and the pumping performance is enhanced. When the pressure is too high， the flow region of the secondary fluid is compressed due to the increase of the expansion core and the entrainment ratio decreases obviously. With the increasing of the primary fluid pressure， the choking position and the shock wave moves downstream. The pumping performance of the ejector is strengthened. The entrainment ratio decreases with the increase of the back pressure. When the back pressure is too high， the reflux phenomenon is obvious and the pumping performance decreases sharply until it loses efficiency. The results indicated that the reasonable selection of the operating parameters can not only improve the pumping efficiency and exhaust capacity of the ejector， but also greatly improve the refrigeration efficiency of jet refrigeration system and reduce the energy consumption.

Key words: ejector, choke, shock wave, entrainment ratio, back pressure

CLC Number:

TQ021

HAN Yu， GUO Li-xin， WANG Xiao-dong， ZHANG Guang-li. Influence of Operating Parameters on the Ejector Performance Based on CFD Simulation[J]. Journal of Northeastern University Natural Science, 2019, 40(11): 1595-1599.

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