Flow pattern transition of thermal-solutal capillary convection with the capillary ratio of-1 in a shallow annular pool
Flow pattern transition of thermal-solutal capillary convection with the capillary ratio of-1 in a shallow annular pool
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DOI：
10.1016/j.ijheatmasstransfer.2015.11.067
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发表时间：
2016-04-01
影响因子：
5.2
通讯作者：
Wu, Chun-Mei
中科院分区：
文献类型：
--
作者：
Chen, Jie-Chao;Li, You-Rong;Wu, Chun-Mei
为了了解流型转变过程，对同时存在径向温度梯度和溶质浓度梯度的环形池中热溶质毛细对流进行了一系列三维数值模拟。毛细管比率固定在-1。工作流体是甲苯/正己烷混合物，普朗特数为5.54，施密特数为142.8。结果表明，当热毛细雷诺数较小时，液池中存在静态导热状态。随着热毛细雷诺数的增加，流动依次分叉为三种不同的振荡流，行波、行波与驻波的组合以及振动轮辐图案。对于行波和行波与驻波的组合，振荡频率单调增加。此外，波数是独立的热毛细雷诺数。这些复杂的流型是由于局部毛细比沿着自由表面的不同分布造成的。(C)2015爱思唯尔有限公司版权所有。
In order to understand the flow pattern transition processes, a series of three-dimensional numerical simulations for thermal-solutal capillary convection in an annular pool subjected to simultaneous radial temperature and solutal concentration gradients were conducted. The capillary ratio was fixed at -1. The working fluid was the toluene/n-hexane mixture with the Prandtl number of 5.54 and the Schmidt number of 142.8. Results show that there exists a quiescent conductive state in the liquid pool when thermocapillary Reynolds number is small. With the increase of thermocapillary Reynolds number, the flow bifurcates orderly into three different kinds of the oscillatory flows, i.e., the travelling wave, the combined travelling wave with stationary wave, and the vibrating spoke pattern. The oscillatory frequency increases monotonously for the travelling wave and the combined travelling wave with stationary wave. Furthermore, the wave number is independent of the thermocapillary Reynolds number. These multiple complicated flow patterns are due to the different distributions of the local capillary ratio along the free surface. (C) 2015 Elsevier Ltd. All rights reserved.