重力场对液池内热-溶质毛细对流影响的数值研究

Numerical Simulation of gravity ekkect on Thermo-solutocapillary Convection in Rectangular Cavity

中文关键词: 热毛细对流  溶质毛细对流  重力  双扩散  水平温度梯度

英文关键词: thermocapillary convection  solutal-capillary convection  gravity  double-diffusive  horizontal temperature gradient

中文摘要:

      数值研究了不同重力场下液池内耦合热-溶质毛细对流流动特性,模型中考虑了热毛细效应和溶质毛细效应相当这一特殊情况。 计算结果显示,当重力加速度较大时液池内存在周期性迁移的对流涡,而当重力加速度较小时,液池内的对流涡迁移消失,因而重力加速度能够促使热-溶质毛细对流失稳。 随着重力加速的减小,监测点的温度和浓度振荡幅度减小。 常重力条件下自由表面速度分布受浮力对流控制;微重力条件下,自由表面的速度分布基本一致,随着重力加速度减小自由表面速度略微减小。

英文摘要:

      Thermo-solutocapillary convection in a rectangular liquid cavity under various gravity levels was investigated by numerical simulation, in which the thermal Marangoni effect is equal to the solutal Marangoni effect. The computational results show that, there is a convective cell traveling in the liquid layer if the gravity level is larger, however, under the condition of a small gravity level the convective cell traveling disappears. The gravity acceleration can cause the thermal and solutal-capillary convection to be instable. With the decrease of gravity, the oscillatory amplitude of temperature and concentration at the monitoring point is reduced. Under normal gravity level the velocity distribution on the free surface is dominated by buoyant convection, however, the free surface is controlled by thermal and solutal-capillary convection on the microgravity level. Moreover, with the gravity level decreases the velocity on the free surface decreases slightly.