Numerical Calculation of the Off - design Aerodynamic Performance on the Multi - stage Axial - flow Compressor

A multi-stage axial-flow compressor with new blades was simulated with commercial software NUMECA.The Spalart-allamaras was adopted as the turbulence model,the multi-grid technique and the smooth residual method were used for reducing the time of the calculation.The off-design performance was computed on the base of the rated condition point.The calculation results and the experimental values were compared and analyzed.The experimental curve and the calculated curve were consistence in the trend.The flow mass of the calculation was more than the experimental with the same comperession ratio.Near the rated operating point,the flow deviation was below 3%,far away from the rated operating point,the flow deviation was about 5%;For predicting surge margin,using NUMECA to further improve the outlet static pressure can approximate the point of divergence,which can be regarded as the stall,combined with the calculation by the software NREC,can get corresponding surge margin.