An implicit surface tension model for the analysis of droplet dynamics

The present work introduces a model which includes an implicit surface tension term in an adopted Lagrangian incompressible framework. The model is applicable to any model where the interface is represented by a moving boundary mesh. The Lagrangian framework is adopted to model the fluid and track its boundary, and the implicit surface tension term is used to introduce the appropriate forces at the domain boundary. In addition, stability is achieved even at time steps up to 20 times larger than the ones previously reported in the literature. Some examples including static, dynamic, and sessile droplets are simulated. The numerical results are capable of reproducing the pressure distribution in droplets, and the advancing and receding contact angles evolution for droplets in varying substrates and inclined planes.