叶轮机械中间隙流与通道二次流相互作用的数值研究

采用数值解法对一压气机静叶栅中叶顶泄漏流与通道二次流的相互作用进行研究 ,详细揭示了在顶部区通道涡、泄漏涡及分离涡的生成和发展。结果表明 ,由于泄漏流动与通道二次流动的方向正好相反 ,适量的泄漏流动可以在一定程度上起到削弱通道涡强度、改善顶部区流动状况的作用。

Numerical Study of Interaction between Clearance Flow and Passage Secondary Flow in Turbomachinery

In this paper,the interaction between tip leakage flow and passage secondary flow in a compressor stator was investigated by numerical method.The calculations are based on the 3D Navier-Stokes equations expressed with nonorthogonal curvilinear coordinates and corresponding nonorthogonal velocity components, and the explicit time marching algorithm and Baldwin-Lomax turbulence model are adopted.An efficient integral H-grid is employed to solve the grid singularity in the tip region.The details of generation and development of passage vortex,leakage vortex and tip separation vortex were predicted.The computed results show,because the direction of the leakage flow is opposite to that of the passage secondary flow,proper leakage flow can weaken the intensity of passage vortex and improve the flow in tip region.