NUMERICAL STUDY OF DROPLET IMPACT ON WETTABILITY PATTERNED SURFACE

Droplet spreading on a surface is a natural phenomenon and found enormous applications in electronic chip cooling, lab on a chip, inject printing, spray cooling to name a few. Most of the numerical work of the droplet impingement phenomena have been studied in the literature for isotropic surface wettability condition where contact angle is uniform for the whole solid surface. We focus on the droplet impingement phenomena for anisotropic surface wettability condition, where a solid surface has different contact angles in different locations. Droplet spreading depends on the Weber number (We), Reynolds number (Re), and the surface properties. The low wetting surface has a high tendency to repeal the liquid, whereas more wettable surface tends to attract the liquid. By wettability patterning the solid surface, we can control the droplet spreading after the drop impact on the surface.