端壁附面层抽吸对对转压气机性能的影响 *

Effects of Endwall Boundary Layer Suction on a

关键词:  对转压气机  端壁附面层抽吸  数值计算  抽吸流量  级环境

Key words:  Counter-rotating compressor  Endwall boundary layer suction  Numerical computation  Suction flow  Multistage environment

摘要:

以双级对转压气机为研究对象，通过在两排转子机匣处开设抽吸孔，采用数值方法研究了不同抽吸流量下端壁附面层抽吸对压气机性能的影响，为吸附式压气机优化设计提供参考。计算结果表明:在级环境下端壁附面层抽吸可以提升压气机失速裕度，但抽吸流量过大会对效率造成一定损失，当抽吸1.6%流量时失速裕度提升了3.8%，压气机性能达到最佳；失速主要由间隙泄漏涡引起并首先在第二排转子叶尖发生，抽吸削弱了泄漏涡的强度推迟失速发生；端壁附面层抽吸增大了叶尖流通能力，使转子叶尖效率和压比得到提升，并有效改善了出口导叶流场。

Abstract:

To provide a reference for design and optimization of the aspirate compressor，the performance and detailed flow structure of a counter-rotating compressor were numerically investigated under different suction flow with endwall boundary layer suction through the two rows of suction holes in the casing over the rotor tip. The results show that in multistage environment endwall boundary layer suction can increase compressor stall margin，but the adiabatic efficiency would be adversely affected by excess suction flow. The compressor performs best under 1.6% suction rate while the stall margin increased by 3.8%. Stall is mainly induced by the leakage vortex，and occurs in the tip area of the second row of rotor at first. The suction can weaken the strength of leakage vortex and delay the stall. Since the end wall boundary layer suction increases the flow capacity，the pressure ratio and adiabatic efficiency are increased，meanwhile the flow field in outlet guide vane tip has also been improved.