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计算了等速上仰ＮＡＣＡ００１２翼型动态失速过程的流场结构，在准定常假设下对失速主涡形成的分离泡进行了绝对／对流不稳定性分析．随攻角增大，失速主涡流场经历了对流不稳定到绝对不稳定的变化．当绝对不稳定区增大到覆盖整个分离泡时，流场从整体稳定转变到整体不稳定，出现涡量二次尖峰状喷发，切断了主剪切层，主涡随之脱体，导致动态失速
The flow field structure of the NACA0012 airfoil dynamic stalling process at constant velocity is calculated. The absolute / convection instability analysis of the separation vortex formed by the main vortex of the stall is carried out under the quasi-constant assumption. As the angle of attack increases, the main eddy current field undergoing stall undergoes a change from unstable convection to absolute instability. When the absolute unstable region increases to cover the entire separation bubble, the flow field changes from the overall stable to the overall instability, and the secondary spike-like eruption of vorticity occurs. The main shear layer is cut off and the main vortex becomes detached, which leads to the dynamic Stall