In order to investigate the vortex structures of multiphase flows around a porous plate,the flow characteristics of gas-liquid two-phase crossflows were numerically simulated by using the RNG k-ε turbulence modeland the Level Set model.The simulated results are compared with the experimental results.The research results show that the separation point and the horseshoe vortex are formed since the crossflow is blocked by gas jet,which can be observed at the upstream of the jet hole.With the increases in the distance away from the wall,the separation point gradually gets close to the jet exit hole.The crossflow detours the jet and forms two counter-rotating vortices on the lateral edges of jet,and the vortex evolution depends upon the distance away from the wall.The counter-rotating vortex pairs (CVP) are formed in the jet region.The development process of the vortex pairs can be devided into 3 stages:in the near wake-region (i.e.,close to the edge of the jet exit hole),the counter-rotating vortex pairs gradually form on the wall,and the increases in the heights of the vortex cores ae well as the distance between the cores lead to the expansion of vortex area.As the flow develops toward downstream,the area of CVP shrinks and even disappears entirely.Further downstream,the CVP appears again on the top of the jet corresponding to the formation of secondary vortex pairs in the near-wall region.%为了研究通气气体与液体两相流旋涡特性,采用RNG k-ε湍流模型并结合Level Set界面捕捉方法,对绕多孔孔板气体与液体两相横射流流动特性进行了数值模拟,并与实验结果进行了比较.研究结果表明:液相横流受到射流气体的阻碍作用在孔口上游、形成分离鞍点和马蹄涡,此分离鞍点随距壁面高度的增加逐渐靠近孔心,形成分离线;液相横流绕过射流气体后形成两个较为封闭的分离旋涡,此分离旋涡随距壁面高度的增加逐渐远离孔心.射流气体内部反旋转涡对的发展过程可分为3个特征阶段:流动位于孔口附近时,反旋转涡对从壁面逐渐形成,涡核间距和高度不断增大,影响面积不断扩张;随着流动向下游发展,反旋转涡对影响面积不断收缩直至消失;当流动发展至下游某一位置时,反旋转涡对在射流气体顶端再次形成,随着反旋转涡对的不断发展,在平板壁面诱导出2次涡对.
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