机匣处理改善某单级跨声轴流压气机性能的机理研究

Study on the flow mechanisms of casing treatment on a transonic single stage axial-flow compressor

采用全三维数值方法研究了轴向倾斜缝机匣处理对某单级跨声轴流压气机性能的影响.数值结果表明:机匣处理不仅扩宽压气机稳定工作范围,而且还略微提高了单级跨声轴流压气机峰值效率.通过详细分析压气机转子内部流场,揭示了该机匣处理对该单级跨声轴流压气机性能及流场影响的机理,在倾斜缝中形成的回流作用下,使叶顶吸力面气流分离的起始位置向下游推移,并削弱了分离流与叶顶间隙泄漏流相互作用造成的恶劣影响,提高了叶顶通道的流通能力,进而推迟压气机失速的发生.

The influences of axial skewed slot casing treatment on the performance of a transonic single stage axial-flow compressor were investigated through three-dimensional（3-D） numerical method.The numerical results indicate that the stable operating range of axial compressors is enlarged and the compressor efficiency is increased with casing treatment appreciably.The flow mechanisms of affecting compressor performance were obtained by analyzing in detail the flow-filed in compressor rotor with casing treatment.It was found that the starting location of flow separation near rotor blade suction was moved backward by the back flow formed in the slots,which weakened the adverse influence rooted in interaction of separated flow and tip leakage flow and improved the current ability of blade tip passage.So the compressor stall was suspended.