Abstract: To control and reduce the leakage loss of the rotor by the tip clearance，detailed experiments have been carried out to investigate the effect of the tip clearance flow in a turbine cascade with different width of pressure-side winglets. The flow field of the cascade outlet and the static pressure distribution on the blade surfaces have been detailed surveyed with different incidences (±10°，±5°，0°). The results show that，as the incidences change from negative to positive，the leakage vortex weaken and the leakage loss decreases，the passage vortices and their losses are strengthened. Pressure-side winglet has a certain effect with all different incidences. The PW0.3 scheme is the best with the design and the smaller incidence ，it can make the total loss of the cascade reduced 10.38% and 8.11%.As the change to the incidence range is larger，the PW0.4 scheme's effect is better.

Key words: Turbine cascade；Incidence；Pressure-side winglet；Tip leakage；Experimental investigation

摘要： 为了控制和降低涡轮动叶由叶顶间隙所引起的泄漏损失，对加装不同宽度压力面小翼的涡轮叶栅间隙流场进行了实验研究，详细测量了±10°，±5°，0°冲角时涡轮叶栅出口流场和叶片表面静压分布情况。结果表明:随来流冲角由负到正，泄漏涡强度减弱，泄漏损失降低；通道涡强度增强，其引起的损失增大。压力面小翼在不同冲角下均对叶顶泄漏流动具有一定的控制作用，在设计冲角和较小的正冲角工况下PW0.3方案压力面小翼作用效果较好，分别使叶栅总损失降低10.38%和8.11%。在冲角变化范围更大时，PW0.4方案压力面小翼效果更好。

关键词: 涡轮叶栅；冲角；压力面小翼；间隙泄漏流动；实验测量