叶顶微射流对小型高负荷离心压气机性能及流场结构的影响

Taking a compact high-speed centrifugal compressor as research object,the influences of micro jet on the performance of the compressor and the flow field structure of impeller tip were studied by numerical method.The results show that when the jet flow rate is 1% of the design flow rate,the stall margin can be increased by 3.12%,and the stable working range can be expanded by 28.17%.At the design point,the inlet Mach number of the blade tip of the prototype centrifugal compressor is more than 1.8,and there is complex shock wave/tip leakage flow interaction at the blade tip,so the operation stability is poor.The micro jet changes the "λ" shaped shock structure,weakens the strength of the leading edge shock wave,reduces the sweepback angle,and reduces the blade tip load level.The micro jet can suppress the circumferential motion of tip leakage flow and weaken the interaction between shock wave and tip leakage flow.The tip leakage vortex is not prone to rupture and collapse,which greatly enhances the operation stability of compressor.