跨声速轴流压气机径向涡现象与失稳机理

对NASA Rotor 37进行数值模拟并与实验结果对比,计算了堵塞点到失稳点的全部工况,详细探究了跨声速轴流压气机附面层分离规律与失稳机理.研究发现:激波后的吸力面附面层中存在一条径向涡,它增强了附面层分离,使部分靠近吸力面的主流向叶尖堆积.随着工况向失稳点推进,压气机转子叶尖出现两块堵塞区,由叶尖泄漏涡与激波作用引起的堵塞区位于压力面前端,由叶尖泄漏涡与径向附面层分离涡耦合作用引起的堵塞区位于吸力面50%弦长后,两块堵塞区的叠加作用最终引起压气机失稳.

Radial vortex phenomenon and instability mechanism of transonic axial-flow compressor

Numerical investigation was made on NASA Rotor 37 and the result was compared with an experiment. Working conditions from blocking point to stall point were calculated to study the rules of boundary layer separation and the instability mechanism of transonic axial-flow compressor. The research discovers a radial vortex behind passage shock wave in suction side boundary layer, which facilitates boundary layer separation and converges part of airflow near suction side to blade tip. With working conditions go to stall point, blade tip passage is jammed by two pieces of blocking zone; one located in the front of blade pressure side is caused by the interference of clearance leakage vortex and passage shock, while the other located on suction side after 50% chord is caused by the interference of radial vortex and leakage flow. The two blocking zones' expansion arouses instability of the compressor.