Abstract: In order to study the effects of casing optimization contouring on the performance of transonic com. pressor，a transonic rotor was investigated with numerical simulation. Comparison and analysis of the flow fieldnear the tip and the overall performance were performed before and after casing contouring near the design pointand near the stall point. The results show that casing contouring could improve the tip flow field and the compres.sor performance. It is found that the efficiency was improved at the whole working condition by about 0.25% nearthe design point and 0.33% near the stall point. The total pressure ratio was improved by about 1.1% near thestall point，however，the total pressure ratio remained unchanged near the design point. Casing contouring reducedthe loads at the leading edge of the blades and changed the 3D structure of shock wave by making it move back.ward slightly. Near the design point，casing contouring improved the efficiency at most of blade span. After casing contouring，two low pressure circles appeared near the casing which produced the 3D pressure gradient effectsand this changed the vortex form in meridional surface near the circles，and it mitigated the effects of the low ve.locity recirculation zone because of the forward direction gradient. The streamline at the tip became more reason.able and the double-leakage phenomenon disappeared. Near the stall point，casing contouring improved the total pressure ratio at most of blade span and the vortex form did not change，but the position of vortex core changed. The streamline at the tip became more reasonable，while the double-leakage phenomenon did not vanish.

Key words: Transonic rotor；Casing contouring；Double-leakage；Parameterization；Shock wave structure

摘要： 为了研究机匣优化造型对跨声速压气机的性能影响，以一跨声速转子为对象，基于数值方法对近设计点和近失速点下机匣造型前后转子叶尖处的流场和整体性能进行了对比分析。结果表明:机匣造型可以有效改善叶尖处的流动，提高压气机性能；提升了全工况范围内的效率，近设计点的效率提升了约 0.25%，近失速点效率提升约 0.33%；近失速点的压比提高约 1.1%，而近设计点的压比基本不变。机匣造型降低了叶片前缘处的负荷，改变了激波的空间结构，使激波后移。在近设计点下，机匣造型提高了大部分叶展上的效率，机匣附近出现两个“低压环”区，由其产生的三维压力梯度效应改变了此位置附近子午面上的涡形态，流向正压力梯度减轻了叶尖处低速回流区的影响；“二次泄漏”叶尖处的流线流动更合理，现象消失。在近失速点下，机匣造型提高了大部分叶展上的总压比；叶尖处的涡形态没有发生变化，而涡核的位置发生了改变；造型使叶尖处的流线流动更加合理，但是“二次泄漏”现象并没有消失。

关键词: 跨声速转子；机匣造型；二次泄漏；参数化；激波结构