Study on two-dimensional control technology of flow field in high-load compressor cascade test

The boundary-layer attached to the side wall of the linear cascade wind tunnel makes the flow passage contract, which destroys the two-dimensionality characteristic of the cascade flow field. The back pressure gradient of the compressor cascade intensifies the contraction, and the contraction becomes more significant with the increase of load. This paper conducts a numerical study on high-load compressor cascade, studies the factors affecting the two-dimensionality of the cascade blowing experiment and the effect of end wall suction at different axial positions, and explores distributed suction. The results show that the secondary flow at the end wall of the conventional cascade squeezes the main flow, accelerates it, reduces the pressure diffusion, and causes the flow field to be distorted. The total pressure loss deviation is as small as 23%. Front and middle suction can control the two-dimensionality of the cascade as a whole, but the spanwise two-dimensional zone is narrow; the tail suction outlet is wider in the spanwise two-dimensional zone, but it only partially improves the two-dimensionality near the tail edge. The front suction is well controlled at full incidence angle, the middle suction has better negative incidence angle characteristics, and the tail suction flow varies linearly with the angle of incidence. Distributed suction can control the two-dimensionality as a whole and broaden the two-dimensional area, and thus this technique is worth exploring and applying.