机匣处理对跨声速离心压气机性能影响

Effects of Casing Treatment on Performance of Transonic Centrifugal Compressor

关键词:  机匣处理  自循环  数值模拟  离心压气机

Key words:  Casing treatment  Self recirculation  Numerical simulation  Centrifugal compressor

摘要:

为了探索自循环机匣处理对跨声速离心压气机影响，利用全三维数值模拟方法对应用自循环上游槽封闭机匣、自循环机匣处理和光滑壁面机匣结构三种情况下的跨声速离心叶轮进行了详细研究。对比结果表明:机匣处理抽吸槽结构本身对离心级的影响很小；自循环机匣处理使得在近失速区域离心级压比和效率有所增加。通过详细的流场分析表明:机匣处理可以降低叶片尖部负荷；自循环机匣处理通过引走叶轮通道内气流并回流到上游，可以延缓叶轮进口攻角的变化和激波的推进，从而延缓离心叶轮的失速。

Abstract:

In order to explore the effects of self recirculation casing treatment on transonic centrifugal compressor，three-dimentional numerical investigations are performed to examine the role of the recirculation device in which upstream slot is sealed，the self recirculation casing treatment and smooth wall in the influence of a transonic centrifugal impeller. The results show that the bleed slot itself has no influence on the compressor，and the self recirculation casing treatment can improve the impeller total pressure ratio and efficiency in the near of stall region. The detailed analysis of the flow field shows that casing treatment reduces the blade loading in the impeller tip region. The self recirculation casing treatment removes the fluid of impeller to upstream，delays the change of incidence at the impeller inlet and shock movement，consequently delays the stall of impeller.