On a new algorithm for incorporating the contact angle forces in a simulation using the shallow water equation and smoothed particle hydrodynamics

•New algorithm to incorporate contact angle force in a SPH Simulation.•Solution of the shallow water equation in partially wetted regions.•Implementation details and comparisons with alternativ algorithms. The simulation of a thin film on a small scale surface that covers only part of the domain must incorporate the contact angle force acting on the border between wetted and dry parts of the surface. A method to reconstruct this contact line and interpolate the resulting force while using smoothed particle hydrodynamics as discretization method is derived, using only geometrical properties to calculate all needed parameters. The method is applied to several test cases to prove its applicability to the simulation of thin films.