匀强电场作用下液滴撞击壁面的动态行为

The Behavior of the Droplet Impinged on the Surface Under the Uniform Electric Field

基于Open FOAM开源软件平台,采用VOF方法耦合电场方程组,数值模拟匀强电场作用下液滴撞击壁面的动态行为,研究电场强度、壁面浸润性对液滴行为的影响,获得电场、流场相互耦合作用下液滴周围电荷密度、电势的分布,重点关注电场力、电荷密度和壁面润湿性对液滴拉伸、撕裂的影响。研究结果表明:电场对液滴运动影响显著,电场力促使液滴拉伸高度增加;随着电场强度增强,电荷集中在液滴尖端,导致液滴喷射现象发生。液滴撞击亲水壁面,底部形成泰勒锥,内部出现涡流,随着壁面浸润性的提高,液滴喷射时间提前,液滴底部不会在疏水壁面上黏接。

Based on the Open FOAM open source software platform,the VOF method is used to couple the electric field equations.The dynamic behavior of droplet impacting on the surface under uniform electric field is numerically simulated,effects of electric field intensity and surface wettability is studied.We obtain the distribution of charge density and electric potential around the droplet,focusing on the influence of electric field force,charge density and surface wettability on droplet stretching and tearing.The results show that:the electric field has a significant effect on the droplet motion,and the electric field force promotes the stretching height of the droplet;as the electric field intensity increases,the charge concentrates on the droplet tip,resulting in droplet ejection.When the droplet hits the hydrophilic wall,a Taylor cone is formed at the bottom,and a vortex appears inside.With the improvement of the wall wettability,the droplet spraying time is advanced,and the bottom of the droplet will not adhere to the hydrophobic surface.