Analytical solutions for modelling the evaporation of sessile drops

An analytical model for drop evaporation in gaseous environments that accounts for the effect of Stefan flow and temperature dependence of the thermo-physical properties is extended to the case of sessile drops. The exact solution to the conservation equations in toroidal coordinates based on the Mehler-Fock transform is reformulated in terms of simple functions by using the method of images for specific values of the contact angle. The method is then extended in approximate form to general values of the contact angles. The accuracy of this approximation is quantified for hydrophobic and hydrophilic cases, thus showing the applicability of the model to a wide range of wettability conditions.