缝式机匣处理对对转压气机的扩稳机理

为探索缝式机匣处理在对转压气机中的适用性，采用数值模拟的方法研究了缝式机匣处理对对转压气机气动性能和稳定裕度的影响。通过分析缝式机匣处理对压气机总体性能和叶尖流场的影响，以揭示缝式机匣处理在对转压气机中的扩稳机理。研究表明：缝式机匣处理可以提高对转压气机的失速裕度，机匣处理的轴向位置对对转压气机的气动性能和失速裕度有显著的影响。随着机匣处理的前移，对转压气机峰值效率的亏损逐渐减小，而失速裕度改善程度相差不大。机匣处理缝的抽吸和射流效应减弱了转子R2叶顶通道的堵塞程度，通过抑制叶尖泄漏流和二次泄漏流的发展以推迟失速的发生，进而实现扩稳。此外，缝式机匣处理时可能改变该对转压气机的最先失速级，同时也证明了缝式机匣处理在变工况下扩稳的有效性。

Mechanism of stability improvement with slot casing treatment in counter-rotating compressor

In order to explore the applicability of slot casing treatment in counter-rotating compressors, the effects of slot casing treatment on the aerodynamic performance and stability margin of a counter-rotating compressor were investigated by numerical simulation. The effect of the slot casing treatment on overall performance of the compressor and tip flow field was analyzed to reveal the stall margin improvement mechanism of the slot casing treatment in the counter-rotating compressor. The study showed that the slot casing treatment can improve the stability margin of the counter-rotating compressor, and the axial position of the casing treatment had a significant impact on the aerodynamic performance and stability margin of the counter-rotating compressor. With the forward movement of the casing treatment, the peak efficiency loss of the counter-rotating compressor gradually decreased, while the stall margin improvement was not much different. The combined effect of bleed and injection of the slots slowed down the degree of blockage in the rotor R2 blade tip passage, and achieved stability improvement by suppressing the development of tip leakage flow and secondary leakage flow. In addition, the slot casing treatment may change the first stall stage of this counter-rotating compressor, demonstrating the effectiveness of slot casing treatment in the expansion of stability under variable operating conditions.