Effect of circumferential groove casing on the response to distortion of an axial flow compressor rotor

Based on an assumed steady inlet circumferential total pressure distortion,the effects of circumferential groove casing treatment on the response to steady inlet circumferential total pressure distortion of an axial flow compressor rotor are investigated numerically for the NWPU axial flow compressor.The results show that,with clean inlet flow,the tip leakage vortex is weakened or even destroyed due to the effects of circumferential groove casing treatment,thus the stall margin of compressor is improved.In addition,with inlet circumferential total pressure distortion,the changes of attack angle due to distortion make the load of several blades too high and then stall happens.The main influence zone of circumferential groove casing treatment is in the tip of blade.Circumferential groove casing treatment cannot improve the stall margin of this compressor rotor under inlet circumferential total pressure distortion.