平面叶栅是透平式叶轮机械的基本物理模型和重要组成部分，流动不稳定是影响叶栅性能和叶轮机械运行稳定性的关键难题，其主要原因之一是分离剪切流失稳导致的流动非定常波动。目前国内外研究主要集中于流动失稳后非定常流动规律的分析，但对失稳过程中不稳定模态扰动的表征及其敏感性特征等关键科学问题的研究较少。. 项目以离心压缩机可调进口导叶为研究背景，从稳定性和敏感性分析、非定常计算和实验等方面对其基本模型——平面叶栅的内部分离剪切流失稳及流动控制策略开展系统深入的研究。分析来流条件和叶栅几何参数对不稳定模态扰动特征的影响，建立流动非定常波动与不稳定模态扰动发展的时空关联，揭示敏感性矢量参数的空间分布规律，实现抑制非定常波动的流动控制，掌握控制方式和参数对控制效果的影响。从扰动发展这一独特角度揭示平面叶栅分离剪切流失稳的力学机理，为实现可调进口导叶分离流动失稳控制提供全新思路。

The planar cascade is the basic physical model and key component for turbomachineries. The flow instability is the main problem affecting the performance of the cascade and the operational stability of the turbomachinery, which could be caused by the unsteady fluctuation resulted from the destabilization of the separated shear layer. Most of the current researches focus on the analysis of flow pattern for the unsteady flow, while there are relatively less studies on the key scientific problems including the characterization of the unstable mode perturbation and its sensitivity pattern.. The project is based on the adjustable inlet guide vanes used in centrifugal compressors as the research background, and performs systematic and comprehensive study on the destabilization and control of the separated shear layer flow in the planar cascade through the stability and sensitivity analysis, unsteady flow simulation and experiment. The influences of the incoming flow pattern and geometrical parameters of the planar cascade on the unstable mode perturbation are analyzed; the temporal-spatial correlation between the unsteady flow fluctuation and the unstable mode perturbation is established; the spatial distribution pattern of the sensitivity vector quantity is revealed; the flow control in suppressing the flow fluctuation is realized; the effects of control strategy and parameters are studied. The inherent mechanism of the destabilization of the separated shear layer flow in the planar cascade is revealed from the distinctive viewpoint of the development of the perturbation, which provides new ideas in the controlling of separated flow destabilization in the adjustable inlet guide vanes.