Effect of endwall suction on aerodynamic performance of compressor cascade with tip clearance at a large incidence angle

Abstract

In order to deeply analyze the application prospect of the boundary layer suction technique on the compressor, the flow control effect of endwall suction scheme on the tip leakage flow of a compressor cascade at a large incidence angle with complex internal flow structure and different loss proportion from the case at design incidence angle, was studied numerically, as well as on the overall aerodynamic performance. The results show that the suction scheme directly affects the structure of the tip leakage flow and makes the onset position of the tip leakage vortex move backward, which weakens the intensity and influence range of the tip leakage flow, thus improving the cascade performance in the tip region. At the large incidence angle, large flow suction makes the boundary layer separation in the low span area advance, and the corner separation region at the gap-free end expands to the upper. The position of the separation vortex shedding rises from 10% blade span under the condition without suction to about 70% blade span under the condition with the suction flow rate of 0.7%, and the separation loss increases. The overall performance of the cascade at the large incidence angle mainly depends on the increase of separation loss, while the effect of the decrease of leakage loss on it is greatly reduced. With suction, the total pressure loss coefficient of the cascade increases by about 5.7% at the incidence angle of +8°.