Effect of Rotor/Stator Axial Loading Design on Compressor Performance and Flow Stability

Abstract

Abstract. Numerical investigations were conducted to study the influence of rotor/stator blade loading distributions (BLDs) on compressor aerodynamic performance. The fore-loaded rotor design slightly improved compressor efficiency at operating conditions above the design mass flow point. Both aft-loaded rotor and aft-loaded stator designs demonstrated performance enhancements at operating conditions below the design mass flow point, with the aft-loaded stator configuration showing more pronounced improvements. Separate analyses of rotor and stator characteristics revealed that differences in stage performance at high mass flowrates were primarily attributed to variations in rotor characteristics. At low mass flow conditions, the significant performance improvement of aft-loaded stator mainly originated from stator characteristics, while the modest enhancement of aft-loaded rotor principally resulted from rotor characteristics. Further analysis identified that the sharp performance degradation in stator characteristics was caused by large-scale flow separation on the stator suction surface. Unsteady computational results demonstrated that changes in rotor BLD affected the stator passage flow through wake interactions, while the aft-loaded stator reduced leading-edge loading and consequently weakened the interference effects between rotor wakes and stator leading-edge separation. A flow stability prediction model was employed to evaluate how different loading distributions impact compressor flow stability. The predictions indicated that aft-loaded rotor design significantly reduced stall inception mass flow and improved flow stability by decreasing rotor tip loading and weakening tip leakage flow intensity. Experimental tests were performed to validate the reliability of both numerical simulations and model predictions.