Design and numerical simulation analysis of a miniature Mixed-flow compressor

Abstract

This paper completed the pneumatic design of a mixed-flow compressor, adopted RANS turbulence model, and chose Spalart-Allmaras model to complete the numerical simulation of the flow field of the S1 flow surface, meridian flow surface, and impeller surface, and then analyzed the working performance at 90%, 100%, and 110% design speed to explore whether the mixed-flow compressor technology suitable for micro turbojet engines as well as the internal flow field flow state and loss mechanism. The results indicate that the shock wave at the front edge of the main blade and the low energy gas gathered at the tail edge of the main blade and the shunt blade, which causes serious flow blockage, are the main causes of the instability of the mixed-flow compressor at the design point. At 100% design speed, the compressor has higher reliability, stronger adaptability, and the best working performance for its working margin, isentropic efficiency, and pressure ratio with lower loss. The results may provide some references for the further optimization design of the current compressor.