Numerical simulation of effect of inlet total-pressure distortion on subsonic axial-flow compressor

3-D steady and unsteady numerical simulations of the effect on the subsonic axial-flow compressor with the three types of circumferential total-pressure distortion of 1 × 120°, 2 × 60° and 5 × 24° have been performed in the full paper. Detailed analyses of the flow field inside the compressor rotor help to draw the following preliminary conclusions: the circumferential total-pressure distortion exerts small effect on the performance of the compressor rotor but has more effect on its stall margin. The loss of stall margin for 1 × 120° circumferential total-pressure distortion is as tremendous as about 7%, while those for 2 × 60° and 5 × 24° ones are about 3% and 1.5% respectively. At the boundary between distortion area and non-distortion area, there exists apparent circumferential flow, and its direction is from non-distortion area to distortion area. The load on the rotor blade decreases when the rotor blade enters the distortion area. However, the load increases when the rotor blade goes away from it. The circumferential inlet total-pressure distortion reduces the chock mass flow and causes total-temperature distortion at the outlet.