In order to clarify dimple induced vortex structure,the fully developed flow be-tween two plane,with a single dimple of classical depth to print diameter ratio of 0.2 placed on the below plane,is simulated with RANS in Fluent.The generation,development and break-down of vortex structure are analyzed with the Zhang Hanxin’s theory of vortex motion bifurca-tion along its axis.And the vortex induce effect after dimple is examined.It is found that the separation belong to a closed separation,in the separation line singular points distribute in spiral/saddle/spiral regularly.When the spiral separation point is generated,wall vorticity is converged to the spiral point and raised in spiral.So the tornado-like vortex is generated perpendicular to the wall.Symmetric tornado-like vortex is closed in symmetric plane,and a half vortex ring is generated.The half vortex ring experienced steady spiral rising,becoming unsteady in the vis-cous dissipation and viscous diffusion,and finally breakdown in the strong adverse pressure gra-dient.After the vortex breakdown,vorticity dispersed and weak longitudinal vortex is induced in the dimple wake which induces upwash in center and downwash in two sides.Rotating in the same direction with longitudinal vortex,induced by upwash in the dimple two sides,edge vortex assisted to enhance convection after dimple.%为了澄清陷窝诱导涡结构及其对尾流的扰动方式，针对布置深宽比0．2陷窝的两平板间充分发展流动进行了稳态数值模拟。应用张涵信的旋涡沿轴线的非线性分叉理论分析表明陷窝内涡结构为失稳破裂的半涡环，总结了陷窝对尾流的扰动方式。研究发现，陷窝诱导的旋涡分离为螺旋点／鞍点／螺旋点分离。物面的分离螺旋点形成，在空间演化为垂直物面发展的对称类龙卷风涡结构。对称类龙卷风涡在对称面闭合形成半涡环。半涡环经历了从稳定升起、沿流向随着涡粘性扩散和涡粘性耗散下变得不稳定、到最后在强逆压梯度下泡型涡破裂的过程。半涡环涡破裂涡量散开诱导形成陷窝尾流的弱纵向涡和陷窝尖后缘绕流产生的边涡旋转同向，加强了陷窝后流场的对流强度。
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