中文摘要：

回流器作为多级离心压气机两级间非常重要的连接部件，其内部的二次流动十分显著。回流器的设计目标是以尽可能小的损失对上一级出口气体进行整流，减小下级叶轮进口处的流场畸变。本文通过对回流器流道和整流叶栅进行参数化建模，采用多岛遗传算法对某多级离心压气机回流器进行基于N—S方程数值求解的三维气动优化设计，着力于提高变工况条件下回流器的级等熵效率以及使变工况条件下回流器的出口气流角尽可能均匀。

英文摘要：

The return channel, in which the secondary flow is highly significant, is a very important connection part between two stages in the multistage centrifugal compressor. The main purpose of the return channel design is to rectify the outlet swirling flow from the former stage with possible little flow loss before it entering the impeller of the next stage. In this work, by parametrically modelling of the meridional path and return vanes, three-dimensional aerodynamic optimization design of the return channel in multistage centrifugal compressor is performed with the multi-island genetic optimization algorithm. The present applications mainly focus on obtaining higher isentropic efficiency and more uniform outlet flow angle distribution of the return channel in various operating conditions.