Direct Numerical Simulation of Air Bubbles in Water/Glycerol Mixtures: Shapes and Velocity Fields
Direct Numerical Simulation of Air Bubbles in Water/Glycerol Mixtures: Shapes and Velocity Fields
复制标题
水/甘油混合物中气泡的直接数值模拟：形状和速度场
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
H. Warnecke
中科院分区：
文献类型：
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作者：
Mario Koebe;D. Bothe;H. Warnecke
本文对高密度比粘性牛顿流体中气泡的上升过程进行了直接数值模拟。模拟进行了高度并行化的代码FS3D，它采用的体积的流体（VOF）的方法。代码的高度并行化允许计算域的高分辨率，使得液相内的柯尔莫哥洛夫长度尺度被解析用于模拟。为了验证的数值结果的终端上升速度，气泡形状和流场进行了比较，实验数据以及近似的解析解。对于高莫顿数终端上升速度和纵横比同意非常好的实验值。对于较低的莫顿数有一个实验和数值上升速度之间的差异越来越大。椭圆形气泡的纵横比与实验测量值和Taylor和Acrivos的理论值相匹配。在非常低的雷诺数（ReB < 1）下，气泡内外的速度场与Hadamard和Rybczynski的蠕动流解析解半定量吻合。
In this paper results of direct numerical simulation (DNS) of bubbles rising in viscous Newtonian liquids with high-density ratio are presented. The simulations are carried out with the highly parallelized code FS3D, which employs the Volume-of-Fluid (VOF) method. The high degree of parallization of the code allows high resolution of the computational domain, such that the Kolmogorov length scale inside the liquid phase is resolved for the simulations. For validation of the numerical results the terminal rise velocities, bubble shapes and flow fields are compared to experimental data as well as to approximate analytical solutions. For high Morton numbers terminal rise velocities and aspect ratios agree very well with experimental values. For lower Morton numbers there is an increasing difference between experimental and numerical rise velocities. The aspect ratios of ellipsoidal bubbles match both with experimental measurements and with theoretical values of Taylor and Acrivos. At very low Reynolds numbers (ReB < 1) the velocity fields in and outside of the bubble show good semi-quantitative agreement with the analytical creeping flow solution of Hadamard and Rybczynski.Copyright © 2003 by ASME