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数值研究了航行体表面等压气膜非定常发展过程及流场旋涡结构.结果表明,等压气膜可分为气相区、混合相区、尾部泄漏区等三个部分,斜孔排气时其轴向、周向尺寸明显增大,气膜轴向推进快、覆盖范围广;在横流与气流间的相互作用下,气相区呈“沙漏”状,排气孔附近存在马蹄涡、绕流分离涡、反向旋涡对等旋涡结构;混合相区以回射流动为特征,膜尾滞止高压及其导致的逆压梯度诱导部分水逆流进入膜内并与气体掺混,流场中出现大尺度的三维壁面涡运动.“,”Numerical study was performed to investigate the unsteady evaluation process of the pressure-equalizing film along an underwater vehicle and the vortex structure in the flow field.The results show that the film can be divided into three zones,namely the air phase zone,the mixed phase zone and the rear leakage zone.Compared to the straight hole exhaust,when air is exhausted from inclined holes,the axial and circumferential dimensions of the pressure-equalizing film increase more obviously and the film advances faster axially to cover a wider range.Under the interaction of water and air,the air phase region presents the shape of an hourglass.The horseshoe vortex,cross-flow separation vortex and counter-rotating vortex pair exist in the vicinity of the exhaust hole.The mixed phase region is characterized by the re-entrant jet flow.The high pressure caused by the flow stagnation in the film tail and its caused adverse pressure gradient induce the water to flow upstream into the film and mix with the air,resulting in a large scale three-dimensional wall vortex motion in the flow field.