机匣处理作用下高负荷轴流压气机转/静子匹配设计研究

In order to investigate the method of axial matching of rotor/stator on a high-loaded axial flow compressor with casing treatment for a further improvement of compressor stability, the effects on compressor performance of the installation angle and the laws of sweep and lean of stators were numerically studied. The flow mechanism of stability improvement was analyzed with the method of unsteady simulations for the combination of casing treatment and optimized stator, and the compressor's stall mechanism was also studied. The results show that the stall of the compressor is triggered by the compressor stator. The compressor's stability can be improved further by optimizing the installation angle or the sweep and lean laws of stators. The stability enhancement is maximized by optimizing the lean law of stators. The compressor's stability is improved by 80.2% and the adiabatic efficiency remains unchanged by the combination of casing treatment and re-designed stator with positively curved blade tip and negatively curved blade root. The compressor stability is improved further by 30.9% compared with the case with only casing treatment. The compressor's stall is triggered by the stator. The boundary layer of suction surface at stator's root is separated under the effect of passage shock. It interacts with the boundary layer of hub surface resulting in a corner vortex. The flow phenomenon of "leading edge spillage, trailing edge backflow" is observed at the operating condition of near stall. The induced blockage in the stator triggers the compressor's stall. The stator should be optimized for a compressor stage under the effect of casing treatment to achieve a better stability improvement.