Numerical investigation of multiple droplet growth dynamics on a solid surface using three-dimensional lattice Boltzmann simulations

Abstract

We present an investigation of multiple droplet growth dynamics on homogeneous and patterned surfaces during dropwise condensation. Our analysis is based on three-dimensional thermal lattice Boltzmann simulations. First, we investigate the growth dynamics on homogeneous surfaces. The analysis of growth dynamics of droplets on a homogeneous surface shows that the lower the static contact angle of the surface, the higher the condensed volume of liquid. After that, we discuss the growth dynamics of droplets on patterned surfaces (a surface with hydrophilic and hydrophobic regions). We show that the pattern formed by the condensed droplets on the patterned surfaces is completely different from the homogeneous surface. This is due to the pinning effect at the interface of the hydrophilic–hydrophobic region. Moreover, the shape of the droplets is not spherical, as we observe in the case of homogeneous surfaces. We also demonstrate that the condensed volume V for all patterned surfaces is higher than that for the homogeneous surface. However, the condensed volume decreases with an increase in the contact angle of the hydrophilic region. We then present the effect of size of the hydrophilic spot. We find that the condensed volume increases with an increase in radius of the hydrophilic spot.