附着滴在粗糙多孔介质表面铺展渗透的数值研究

Numerical Analysis of Spreading and Penetration of Adhesive Drops on Rough Porous Media

为了探究附着滴在粗糙多孔介质表面的动力学行为,课题组通过ANSYS FLUENT对液滴在多孔介质上的铺展渗透进行了研究。首先用凹凸槽来代替表面粗糙度的方法,然后使用VOF模型追踪液滴形态变化,最后利用PISO算法进行数值模拟计算。定量分析了邦德数、平衡接触角、达西数和多孔介质表面粗糙度对液滴铺展半径和渗透深度的影响。结果表明:随着液滴邦德数的增大,液滴更易变形,铺展和渗透深度增加;随着平衡接触角的增大,液滴越难铺展和渗透,但液滴后期阶段渗透深度增加;随着达西数增大,多孔介质的渗透率增大,所以渗透深度增加,而铺展半径相对减小;随着多孔介质表面粗糙度的增大,铺展半径减小,渗透深度增大。该研究的成果有利于提高生产质量和减少环境污染。

In order to investigate the dynamic behavior of adhesive droplets on the surface of rough porous media,ANSYS FLUENT was used to study and analyze the spreading and penetration of droplets on porous media.Firstly,the concave-convex groove was used to replace the surface roughness method,and then the VOF model was used to track the droplet shape change,and finally the PISO algorithm was used for numerical simulation calculation.The effects of Bond number,equilibrium contact angle,Darcy number and surface roughness of porous media on the spreading radius and penetration depth of droplets were quantitatively analyzed.The results show that as the bond number of the droplet increases,the droplet deforms more easily,and the spreading and penetration depth increases;with the increase of the equilibrium contact angle,the droplet spreads and penetrates more difficultly,but the penetration depth at the later stage of the droplet increases;as the Darcy number increases,the permeability of the porous media increases,so the penetration depth increases,while the spreading radius relatively decreases;with the increase of the surface roughness of the porous media,the spreading radius decreases and the penetration depth increases.This research will help improve production quality and reduce environmental pollution.