竖直表面液滴运动的数值模拟

Numerical Simulation of Moving Droplets on Vertical Walls

为研究具有不同润湿特性的表面上液滴运动的规律,本文依据液滴接触角与基底方位角的关系以及运动液滴的动态接触角模型,运用Fluent软件,实现了对竖直表面上静止和运动液滴的数值模拟,得到了液滴的形貌以及内部的速度分布。模拟所得竖直表面上静止液滴和运动液滴的接触角和形貌均与实验结果吻合较好。液滴内部速度分布表明,裸铝表面(亲水)上液滴的运动方式为滑动;114°疏水表面上的液滴内部出现不完整的环流,但仍然以滑动运动为主;而145°疏水表面上液滴以滚动方式向下运动,液滴运动较快。

This paper considers the relationships between droplet contact angles and azimuth angles and the dynamic contact angle models for moving droplets to simulate the droplet motion on vertical walls to investigate the droplet motion characteristics on surfaces with various wettability with the droplet morphologies and the velocity distributions obtained.The results show that the simulated droplet morphologies and droplet contact angles of both the static droplet and the moving droplet are in good agreement with the experimental results.The velocity distributions of moving droplets indicate that the droplet slips over a bare-Al surface which is hydrophilic.The droplet still slips over a surface with 114° contact angle with circumfluence partially occurs,while the droplet rolls down rapidly a surface with 145° contact angle.