Optimization and verification of droplet infiltration model in contact line theory

Abstract

In order to improve the theory of contact line density, the contact angle model of rectangular convex structure with anisotropy was established, and the integral method and cyclic assignment method were used to solve the droplet volume. Then, the characteristic dimensions of FKM (fluorine rubber) surface prepared by template method were collected by visual recognition technology. In addition, the gravity, surface tension and micro-droplet height of the droplet in the antenna model were verified. Finally, the error of theoretical droplet height and actual droplet height in the solution of droplet gravity and surface tension was calculated by regression model. It is shown that the empirical correction coefficient of the contact angle model is 0.04–0.112 when the droplet gravity and surface tension are equal. Moreover, the reliability of theoretical gravity and theoretical surface tension of droplets instead of actual values is 96.3% and 99.4% respectively. States of droplets on six FKM surfaces are all in accordance with Wenzel-Cassie transition state model. Optimizing the theory of contact line density is conducive to designing accurate and anisotropic rough structures.