关键词: 激波/附面层干扰;超声速压气机叶栅;角区分离;附面层抽吸;附面层吹气

Abstract: Boundary layer suction and air injection are among the proved methods of controlling flow separation and improving blade loading of compressors. In this study, different endwall suction/air injection schemes were designed and investigated in a supersonic compressor cascade, in order to reveal the control mechanism of shock wave induced corner separation and the difference between endwall suction and air injection. Results show that significant area of corner separation appeares in the supersonic compressor cascade passage under shock wave/boundary layer interaction. Because of the influence of severe corner separation, the single-normal passage shock wave in the two-dimensional cascade changes to a double-shock wave (an oblique shock wave and a normal shock wave) in the mid-span of the three-dimensional supersonic compressor cascade, and the open separation changes to a closed separation on the suction surface near the trailing edge. Endwall suction can effectively control the corner separation, the loss coefficient near the endwall is reduced significantly. The optimal endwall suction scheme is the same with subsonic compressor cascade in the open literatures. After endwall suction, the double-shock wave in the mid-span changes to a single-normal shock wave, and the separation near the trailing edge of the mid-span is enlarged. Endwall air injection can also effectively reduce corner separation of the supersonic compressor cascade, and the control effects is superior to endwall suction, which is because the static pressure at the air injection slot are higher than that at the suction slot. The optimal endwall air injection scheme is located at the leading edge of the cascade.

Key words: Shock wave/boundary layer interaction;Supersonic compressor cascade;Corner separation;Boundary layer suction;Boundary layer injection