Effect of blade trailing edge filing on aerodynamic performance of centrifugal compressors

To study the effect of blade trailing edge filing on aerodynamic performance of centrifugal compressor by CFD, filing was applied on blade pressure side or suction side of a high pressure centrifugal impeller. The results show that, blade trailing edge filing changes the blade angle of pressure side or suction side and the flow field at the impeller outlet. The filing on the pressure side decreases the pressure ratios of both impeller and compressor stage, but it increases the stage efficiency. Inversely the filing on the suction side improves the pressure ratios of both impeller and compressor stage, but it almost has no effect on the efficiency. The effect of blade trailing edge filing is associated with the filing position, filing length and filing thickness, and the optimal filing length or filing thickness exists.