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流动分离是关系到叶轮机械运行安全性和经济性的重要流动现象。为了进一步揭示这一复杂流动现象的特性和物理模型，该文应用激光Ｄｏｐｐｌｅｒ测速仪和七孔气动探针对一环形压气机叶栅在大攻角下的流道内部和流道出口的流场进行了实验研究。得到了流动严重分离情况下的流场速度、湍流度、湍流应力、总压损失及静压等重要流场参数的分布和分离区的形态。实验结果揭示： 在分离流动中粘性分离和惯性分离并存； 分离后的流场呈现出主流、剪切流和分离涡流三区共存的特征，其中速度剪切层对叶栅特性产生显著影响； 在分离边界附近，流动参数变化剧烈，可作为判定分离边界的依据。
Flow separation is an important flow phenomenon that is related to the safety and economy of the impeller. In order to further reveal the characteristics and physical model of this complex flow phenomenon, a laser Doppler velocimeter and a seven-hole aerodynamic probe were used to simulate the flow field inside a circular compressor cascade and its outlet at large angle of attack An experimental study was carried out. The distribution of important flow field parameters, such as flow velocity, turbulence, turbulent flow stress, total pressure loss and static pressure, and the shape of the separation zone are obtained under severe flow separation. The experimental results show that the viscous separation and the inertial separation coexist in the separation flow. The separated flow field shows the coexistence of the main flow, the shear flow and the separation vortex. The velocity shear layer has a significant effect on the characteristics of the cascade. Separation of the vicinity of the boundary, the flow parameters change dramatically, can be used as a basis for the determination of the separation boundary.