轴流压气机时尖泄漏涡的时均流动

DEVELOPMENT OF TIP LEAKAGE VORTEX INSIDE AN AXIAL-FLOW COMPRESSOR ROTOR MSSAGE IN DESIGN CONDITION

用三维激光多普勒测速系统测量研究低速大尺寸单级压气机设计状态转子内尖区流场．结果表明，泄漏流在气流一进入转子叶片通道就开始发生，发生于前半弦长，其诱导形成的泄漏涡约在30％弦长处达到最强，随后逐渐衰减，其涡核顺下游慢慢向压力面方向和低时高方向移动，涡核在转子出口移至通道中部．泄漏涡影响区域沿流向逐渐扩大，并向压力面方向和低叶高方向移动．设计状态叶尖泄漏涡在转子尖区流动中起主要作用，是造成尖部流动阻塞的主要因素．

Development of tip leakage vortex inside an axial-flow compressor rotor passage indesign condition was studied using a 3-D Laser Doppler Velocimetry. The flow was surveyedacross the entire passage at fifteen axial locations (leading edge to trailing edge) and twelveradial locations (0.985, 0.980, 0.975, 0.950, 0.925, 0.900, 0.875, 0.850, 0.813, 0.775, 0.738,0.700 span). The measurement results indicated that the tip leakage vortex produces verynear the leading edge, and it becomes strongest at 30% chord, then decays slowly. With thefiow downstream, the vortex core moves to the pressure surface and lower radial location,leading to more and more flow mixing. At the exit of the rotor passage, the lea.kage vortexexists in mid-passage. The tip leakage vortex plays a leading role in the tip flow field of therotor passage, producing most flow blockage.