近失速状态轴流压气机转子内尖区三维流动结构

用激光测速系统测量了低速大尺寸单级压气机近失速状态转子内尖区三维流场。结果表明泄漏流在转子进口开始产生，泄漏涡约在１０％弦长最强，并迅速向压力面和低叶高方向移动，沿程造成高紊流和高阻滞。叶尖吸力面附面层发生分离，迫使角区低能物质和旋涡在下游逐渐向通道中部移动，造成转子出口尖部通道中部大面积流动阻塞和紊流脉动。角区旋涡及泄漏涡影响区域紊流强度较高，其中径向分量最高，远大于轴向和切向分量。前缘马蹄涡压力面分支存在于转子进口叶尖压力面角区，并迅速向低叶高和通道中部移动，约在２０％弦长和泄漏涡交汇。

THREE-DIMENSIONAL FLOW IN THE TIP REGION OF AN AXIAL COMPRESSOR ROTOR PASSAGE AT A NEAR STALL CONDITION

This paper presents an experimental study of the three-dimensional turbulent flow in the tip region of an talal compressor rotor passage at a near stall condition. The investigation was conducted in a low-speed large-scale compressor using a 3-component Laser Doppler Velocimetry. The flow was surveyed across the passage at fifteen talal locations (inlet to outlet) and twelve radial locations (0.985 to 0.700 spans). The measurement results indicated that a tip leakage vortex is produced very close to the leading edge and becomes the strongest at about 10% axial chord from the leading edge. The vortex migrates quickly towards the pressure side, causing substantial flow blockage and turbulence nearby. Flow separation happens on the tip suction surface at about half chord, prompting a corner vortex migrating toward the pressure side. Tangential migration of the low-energy fluids results in substantial flow blockage and turbulence in the rear of a rotor passage. The radial component is the highest of the three turbulence intensities in the corner vortex or leakage vortex region. The pressure- side leg of a leading-edge horse-shoe vortex is found at the inlet tip corner of a pressure surface and mixes with the leakage vortex at the mid-passage of about 20% chord.