跨声速离心压气机多部件耦合优化扩稳

基于最优拉丁超立方采样、多项式代理模型、傅里叶幅值敏感性试验、梯度变异混合优化算法构建了跨声速离心压气机耦合优化方法，实现了自循环机匣处理扩稳的同时不降低等熵效率的目标。耦合优化后压气机气动性能全面提升，设计点和近失速点的等熵效率分别提高2.79%、1.82%，且峰值效率略高于实壁机匣压气机。耦合优化扩稳增效的机理是：自循环机匣抽吸流量增大，更多低能流体被移除；叶轮入口攻角改善，流动分离风险减小；前缘激波与叶尖泄漏涡干涉被抑制，叶轮下游低能流体减少，周向均匀性增强；机匣回流槽入射角增大，叶轮入口径向畸变被削弱；叶轮叶片尾缘安装角及扩压器有叶段尾缘半径的增大弥补了等熵效率损失；叶轮叶片前缘后掠角减小弥补了堵塞流量。

Multi-component coupling optimization for stability improvement of transonic centrifugal compressor

Based on the optimal Latin hypercube sampling, polynomial surrogate model, Fourier amplitude sensitivity test, and gradient mutation hybrid optimization algorithm, a coupling optimization method of transonic centrifugal compressors was constructed, and the goal of self-recirculation casing treatment stability improvement without loss of isentropic efficiency was achieved. After the coupling optimization, the aerodynamic performance of the compressor was comprehensively improved. The isentropic efficiency of the design point and near-stall point increased by 2.79% and 1.82%, respectively, and the peak efficiency was slightly higher than the solid compressor. According to the mechanisms of coupling optimization for stabilization and efficiency enhancement: the recirculation flow of self-recirculation casing treatment was increased, and more low-energy fluid was removed; the flow incidence angle of impeller was improved, and the risk of flow separation was reduced; the interaction of leading edge shock wave and the tip leakage vortex was suppressed, the low-energy fluid downstream the impeller was reduced, and the circumferential uniformity of the flow was enhanced; the injection angle of upstream slot of the casing treatment was increased, and the radial distortion of the impeller inlet was weakened; the increases of both the blade angle of the impeller trailing edge and the radius of the diffuser blade trailing edge made up for the isentropic efficiency loss; the reduction of the back sweep of the impeller blade leading edge made up for the choke flow.