摘要
为了探究双液滴同时撞击粗糙多孔介质表面的动态行为,课题组通过使用凹凸槽来代替表面粗糙度的方法,并用VOF模型追踪液滴形态变化,最后再利用PISO算法进行数值模拟计算。课题组分析了液滴特性和多孔介质特性对液滴铺展长度的影响,以及2液滴碰撞后对射流高度的影响。研究结果表明:随着韦伯数We的增加,液滴射流高度和铺展长度都增加,且在竖直和水平方向都会产生多个二次液滴飞溅;双液滴水平间距越大,液滴的铺展长度越大,射流液柱越低;平衡接触角越大,液滴铺展长度越小,边缘液体越易回缩;达西数Da越大,液滴的铺展半径减小,双液滴合并后形成的射流液柱越低;粗糙度越大,2液滴合并所需要的时间就越长,合并后形成的射流液柱高度变低,铺展长度越小。
In order to investigate the dynamic behavior of double droplets simultaneously impacting the surface of rough porous media, the surface roughness method was replaced by concave-convex grooves, 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 droplet characteristics and porous media characteristics on the spreading length of droplets and the jet height after two droplets collision were analyzed. The results show that as the Weber number increases, the droplet jet height and spreading length increase, and multiple secondary droplet splashes will occure in the vertical and horizontal directions;the larger the horizontal distance between two droplets, the larger the spreading length of the droplets, the lower the jet liquid column;the larger the equilibrium contact angle, the smaller the spreading length of the droplet, and the easier it is for the edge liquid to retract;the larger the Darcy number, the smaller the spreading radius of the droplet, the lower the jet liquid column formed after merging;the greater the roughness, the longer it takes for the merging of two droplets, the lower the height of jet liquid column formed after merging, and the smaller the spreading length.
作者
邓辉良
李培超
DENG Huiliang;LI Peichao(School of Mechanical and Automotive Engineering,Shanghai University of Engineering Science,Shanghai 201620,China)
出处
《轻工机械》
CAS
2021年第3期23-29,共7页
Light Industry Machinery
基金
上海市自然科学基金项目(19ZR1421400)。
关键词
多孔介质
双液滴
铺展长度
射流高度
粗糙度
porous media
double droplets
spread length
jet height
roughness
