某辅助动力装置涡轮盘腔泄漏影响数值研究

Investigation of Cavity Leakage Flow on Turbine Performance in APU

本文采用数值模拟的方法研究了盘腔泄漏流对某型辅助动力装置涡轮部件性能及流场的影响,并分析了其作用机理。结果表明,盘腔泄漏流对涡轮性能有较大影响,泄漏流不影响涡轮进口流量,但会影响功率分配并明显降低涡轮效率。优化搭接结构可减小盘腔泄漏流流量,提高涡轮效率。盘腔泄漏流对二级导向叶片通道流场影响较小,对二级工作叶片的影响主要集中在30%叶高以下区域。盘腔泄漏流促进了二级工作叶片叶根部位漩涡的发展,增大了叶片通道的二次流损失。

This paper presents a numerical investigation of impact of cavity leakage flow on turbine in APU,includes both the flow physics and the consequences on overall performance.It appears that,the cavity leakage flow does not affect the turbine inlet flow mass,but it affects the power distribution between two stage turbine and significantly reduces the overall turbine efficiency.It can reduce the cavity leakage flow and improve turbine efficiency with a optimized cavity structure.The cavity leakage flow influence on the vane passage flow field is very small and the influence on the blade passage flow field is mainly concentrated on the below 30%blade height area.The leakage flow greatly accelerated the blade horse shoes vortex development and increased the secondary flow loss.