Numerical study of the evaporating dynamics of a sessile water droplet

Evaporation dynamics of a sessile water droplet on an ideal heating substrate is investigated numerically. For small droplet radii, gravity can be neglected and the droplet shape assimilated to a spherical cap. Hydrodynamic equations are used for the description of the droplet properties and a finite element method is employed to obtain the corresponding solution. Water-air interface is free and the surrounding air is assumed to be still. The time evolution of the droplet volume and the evaporation rate show clearly non-linear behaviour indicating the existence of unexpected evaporation regimes. Time evolution of the contact angle is used for the estimation of the evaporation time.