A penalization technique applied to the “Volume-Of-Fluid” method: Wettability condition on immersed boundaries

•A penalization approach is applied to the “Volume-Of-Fluid” method.•We focus the study on the wetting effect enforced on the surface of immersed objects.•A spatial shift between boundary conditions is proposed to keep the method stable.•The method is validated on several cases of capillary-dominated flows.

A penalization approach is presented to simulate two-phase flow in the presence of immersed solid boundaries so as to consider highly complex objects such as porous media microstructures. Based on the standard Volume-Of-Fluid formulation, the method takes into account the wettability effects which may occur on the surface of immersed solid boundaries. A spatial shift between the no-slip and the wettability conditions is introduced to make the method stable, regardless of the simulation parameters. The penalized VOF model and the numerical choices are then validated by a series of tests on capillary-dominated flows, which represent the most challenging cases for VOF simulations.