Droplet spreading simulations by using a variational FEM approach

A numerical study on contact angle dynamics during spreading and recoil of droplets impacting orthogonally with various fixed contact angle is presented. This numerical study is based on a finite element variational formulation of the problem and, since the problem is clearly singular, a limiting approach is discussed and the boundary singular condition is imposed as a penalty term. The evolution of the interface is solved over axisymmetric domains by using a new numerical surface tension representation and a new tracking marker technique, which conserves almost exactly the mass. In order to see the capability of the variational model, some numerical solutions are computed for different constant contact angles and for different droplet properties.