高负荷多级轴流压气机级间引气数值模拟

Numerical simulation of inter-stage bleeding in highly-loaded multistage axial compressor

采用数值模拟的方法,以一台高负荷8级轴流压气机为研究对象,研究了级间引气对压气机总体性能、内部流场和级间匹配特性的影响.结果表明:级间引气可以显著提高压气机的总体性能,引气使得压气机进口流量增加近1%,最高效率提高约1.5%;引气会使引气位置处的压力降低,气流密度减小,从而使得引气位置上游的流量增加,转子最大载荷位置向下游移动,引气位置下游的流量减小,而转子最大负荷位置基本保持不变;引气还会使引气位置上下游各级的工作点位置发生变化,改变压气机的级间匹配特性.同时静子尾部机匣处引气还会使引气位置下游机匣处的附面层厚度减小,改变下游转子的进口条件.

Taking a highlyloaded eightstage axial compressor as an object of research, the effect of interstage bleeding on compressor performance, inner flowfield and interstage matching in highlyloaded multistage axial compressor was investigated numerically. The re sult shows that interstage bleeding can significantly improve the compressor＇s performance. The bleeding results in 1% increase of the inlet mass flow and of 1.5 %increase of the high est efficiency. In addition, the bleeding can decrease the pressure and density of air near the bleeding pores. This leads to an increase of mass flow upstream with the largest load position of ro tors moving to downstream as well as a decrease of the mass flow downstream with the largest load position of rotors kept steady proximately. Moreover, bleeding contributes to change the working point position of stages in upstream and downstream of the bleeding position and alter the inter stage matching of compressor. At the same time, bleeding at the trailing edge of stator could dimin ish thickness of boundary layer and change inlet condition of rotor downstream.