Effects of moving endwall on tip leakage flowin compressor cascade

A numerical simulation was carried out to investigate the effect of the moving endwall on the tip leakage flow structure in a compressor cascade with different tip clearances. A detailed comparison of leakage flows loss, trajectory, size and mass flow rate, as well as the tip leakage flow features and its interaction with the mainstream, was conducted. Results showed that the moving endwall led to more leakage mass flow through the gap. The region of the tip leakage vortex was flattened away from the blade suction side. The interaction between the mainstream and the tip leakage flow was weakened. The structure of the vortexes inside the passage was altered. In the small clearance cases, the main effects of the moving endwall were focused on the near wall region. While in the large clearance cases, the moving endwall clearly suppressed the tip separation vortex, thus influencing the velocity distribution of the whole clearance, and further impacting the shear between the mainstream and the tip leakage flow.