进口畸变下新型处理机匣改善压气机性能的机理研究

Investigation on Mechanism of Perfomance Improvement for Compressor with New Type of Casing Treatment

关键词:  进口畸变  压气机  自适应流通  处理机匣  气流分离  前缘溢流

Key words:  Inlet distortion  Compressor  Self adapting recirculation  Casing treatment  Flow separation  Leading edge spilling flow

摘要:

为了揭示进口畸变下,处理机匣改善压气机性能的机理,采用全通道非定常计算方法研究了进口畸变时新型处理机匣-自适应流通处理机匣对亚声速轴流压气机性能及流场的影响,数值模拟中进口总压畸变通过在进口径向段布置栏杆实现。数值结果表明,进口畸变后采用自适应流通处理机匣能够提高转子的性能,其中效率的增加效果比总压比的明显,并获得近6.8%的综合失速裕度改进量。通过详细地分析压气机内部流场表明,处理机匣后使部分叶顶通道吸力面附面层分离起始位置向后缘移动,最大后移距离约为11%叶顶弦长,削弱了叶顶通道由气流分离造成的不良影响,并抑制叶顶间隙泄漏流从相邻叶片叶顶前缘的溢出,当喷气装置对准叶片通道时,其抑制前缘溢流的效果才是最佳的。

Abstract:

Influences of the performance and flow-field of subsonic axial-flow compressor are investigated with full-annulus unsteady numerical method with self recirculation casing treatment under inlet distortion to uncover the flow mechanism. Inlet distortion is made by setting barriers in the inlet radial passage. The numerical calculative results show that besides gaining 6.8% stall margin improvements,the performance of compressor can be improved with self recirculation casing treatment under inlet distortion and the effect of increasing efficiency is better than the effect of increasing total ratio. The fundamental flow mechanism is obtained by analyzing the flow-filed in rotor passage in details. The detailed analysis of the flow-filed in compressor indicates that the separated locations of blades suction boundary in some tip passage move toward blade trailing with casing treatment and the highest value is about 11% the tip chord length,weakening the bad effect of flow separation and preventing leakage flow spill to adjacent tip passage. When injecting setups face the blade tip passage,the effect of restraining tip clearance leakage flow is the best.