速度对液滴撞击超疏水壁面行为特性的影响  

Effect of velocity on behavior of droplet impacting superhydrophobic surface

作　　者：杨宝海[1,2] 王宏[1,2] 朱恂[1,2] 丁玉栋[1,2] 周劲[1,2] 

机构地区：[1]重庆大学工程热物理研究所 [2]低品位能源利用技术及系统教育部重点实验室,重庆400030

出　　处：《化工学报》2012年第10期3027-3033,共7页CIESC Journal

基　　金：国家自然科学基金项目(50906102);重庆市自然科学基金项目(CSTC2011jjA90015);教育部留学回国人员科研启动基金项目(教外司留[2010]1561号);研究生科技创新基金项目(CDJXS11140003)~~

摘　　要：通过可视化实验研究了直径为2.58mm的液滴在不同速度下撞击静态接触角为156°超疏水壁面后的运动特性,其液滴Weber数在8～310之间。实验利用光学原理在同一画面上同时记录了液滴撞击壁面过程的正面及底面图像。实验结果表明:液滴撞击壁面的速度对液滴的前进角、后退角,三相接触线的速度以及液滴反弹后的空中运动特性都有较大的影响;液滴高速撞击超疏水壁面后会产生明显的液指及多组卫星液滴,回缩阶段相邻的液指发生聚并直至液滴完全回缩。Superhydrophobic surface has been widely used both in industry and household products,and attracted intensive attention by researchers.In the present study,a water droplet impacting a superhydrophobic surface with the static contact angle of 156°was experimentally studied at Weber number from 8 to 310.For capturing more information about the whole impacting process,a mirror was set underneath the transparent superhydrophobic surface to simultaneously obtain the images of both the top view and bottom view for the droplet impact and its motion in the air after rebounding.The experimental results showed that the advancing and receding angles as well as the velocity of triple-phase contact ring for the extended droplet on the surface,and the motion pattern in the air of the rebounding droplet were significantly affected by the initial velocity of water droplet.When a droplet impacted the superhydrophobic surface with a high velocity,three groups of satellite droplets were generated during the extension and retraction stages,and the coalescence of neighboring droplet fingers was observed to form a new larger droplet finger during the retraction stage.

关 键 词：超疏水壁面 液滴撞击 动力行为 可视化实验 

分 类 号：O359.1[理学—流体力学]