Based on the detailed computational fluid dynamics (CFD) study on the structure and development of tip leakage flow in NASA(National Aeronautics and Space Administration) Rotor 37

the stall mechanism was discussed.A study of the circumferential grooves casing treatment with different locations

depth and width was also performed.The simulation reveals that the large separation zone at the trailing edge near the blade tip is directly attributable to the compressor stall at the configuration studied in this paper.As a result

the circumferential grooves at the mid-chord and the trailing edge appear to be effective on the extension of the stall margin.Meanwhile

it is found that the depth of the grooves does not influence obviously its effect

while the width seems to be a more important parameter.