封闭容器内液体间界面不稳定对混合过程的影响

Influence of interface instability on liquid mixing process in closed container

该文采用高速摄影和平面激光诱导荧光(PLIF)技术,对圆柱形容器中界面不稳定性对液体混合的影响进行实验研究。使用多相流和湍流模型计算了界面不稳定性的发展情况,分析了不同Atwood数和容器长细比下液体界面不稳定性对液体混合过程的影响。研究发现,界面不稳定性的发展有助于液体间的混合,随Atwood数的增大混合时间增大,容器下层液体(重流体)越难混合。长细比越大越有利于混合,当长细比减小时,容器下层轻流体向上翻转,难以形成利于混合的涡,且造成轻流体残留。

The influence of interface instability on the liquid mixing process in a cylinder container is studied experimentally by using the high-speed photography and the planar laser induced fluorescence（ PLIF） technology. The evolution of interface instability is calculated by applying the multiphase fluid flow and turbulence models. The influence of different Atwood numbers and aspect ratios on the liquid mixing processes is analyzed. The results show that the evolution of interface instability is helpful for the liquid mixing process. The mixing time increases with the increasing of Atwood numbers,meanwhile the heavy liquid is hard to be mixed on the bottom of container. Entirely,the bigger the aspect ratios are,the better the mixing effects are. As the aspect ratios decreasing,the mixing eddies are hard to form during the rolling over process of the lighter liquid,and some remains of unmixing lighter liquid exist.