Effect of Solid-fluid Interaction Parameter on Wettability of Surfaces with Irregular Triangular Micropillars Using Lattice Boltzmann Method

This work aims to conduct a numerical examination of the influence of surface wettability on textured surfaces. To do this, a two- dimensional (2D) pseudo-potential multiphase lattice Boltzmann approach is used, using a D2Q9 model. The solid-fluid interaction parameter (Gads) is varied within the range of -2.20 to -1.20. The numerical model is evaluated by simulating the equilibrium state of a water droplet on a flat surface using different interaction parameters. Subsequently, we proceeded to affix the micropillars onto the lower surface wall, using varying pillar heights. This process facilitated the creation of hydrophobic and superhydrophobic surfaces, enhancing the contact angle. The simulation of surface wettability involves the use of water droplets having a radius of 150 lattice units inside a region of 1000x1000 lattice units. The current research demonstrates that by raising the interaction parameter of textured hydrophobic surfaces, there is a significant decrease in the contact area between water droplets and solid walls and hence decreases wettability. This is attributed to the phenomena of momentum redirection, which ultimately leads to an increase in the hydrophobicity of the surface. Analogous events are seen when the spacing between micropillars is increased, resulting in an increase in the hydrophobicity of the surface.