角区分离是一种常发生于轴流压气机"吸力面-端壁"角区的三维分离现象,该现象以及随之产生的流场堵塞和流场损失会对压气机的稳定工作和效率造成不良影响,严重时会发展为"角区失速"。随着现代轴流压气机单级负荷的提升,角区分离所产生的负面影响日益突出,严重阻碍了高负荷压气机的发展,各种主动、被动流动控制方法也因此被广泛应用于角区分离的流动控制。首先,从角区分离对轴流压气机性能的影响、角区分离的流场特征和角区失速的判别准则3个方面对轴流压气机角区分离的流动机理研究进行了回顾,详细讨论了角区分离的影响因素、角区分离的流动拓扑分析以及角区失速的定义与判别方法。其次,对三维叶片设计、翼刀与凹槽、旋涡发生器、非轴对称端壁造型、射流式旋涡发生器、等离子体气动激励以及附面层抽吸与附面层射流7类流动控制方法的研究进展进行了回顾,重点探讨了这些流动控制方法在抑制角区分离方面的应用,并给出了这些流动控制方法的对角区分离的作用机制。最后,对角区分离领域的研究现状进行了简要地总结,指出了现有角区分离的机理研究和流动控制研究所存在的不足,并对该领域未来的发展进行了展望。
Corner separation is a kind of three-dimensional separation that occurs commonly in the suction-endwall corner area of axial compressors.Corner separation and the associated flow losses and blockages will have negative effect on stability and efficiency of compressors,and will even develop into"corner stall"in severe cases.With the increase of stage loading of modern compressors,the negative effect of corner separation becomes so prominent as to seriously hinder the development of highly loaded compressors.Therefore,many active and passive flow control methods are widely applied to flow control of corner separation.Research progress of the mechanism of corner separation of the axial flow compressor is reviewed from three perspectives:influence of corner separation on performance of the axial flow compressor,flow field characteristics of corner separation and the criterion for corner stall.The influencing factors and the topological analysis of corner separation and the definition and judgment of corner stall are discussed.Research progress of seven flow control methods is reviewed,including three-dimensional blade design,fence/groove,vortex generator,non-axisymmetric endwall profiling,vortex generator jet,plasma aerodynamic actuation,and boundary layer suction/jet.Application of these methods too the suppression of corner separation is emphatically discussed,and the mechanism of these methods for suppression corner separation is given.The research status of corner separation is summarized.The shortcomings of current research are pointed out,and future development of this research field is described.