Fluid-Particle simulations with FreeFem++

Abstract

We present here a method to simulate the motion of rigid particles in a Newtonian fluid. The rigid motion is enforced by penalizing the strain tensor on the rigid domain and the time discretization is performed using the method of characteristics. This leads to a generalized Stokes variational formulation on the whole domain which can easily be implemented from any Finite Element Stokes/Navier-Stokes solver. In order to ensure robustness, we describe a strategy to take collisions into account. To validate the method, simulations implemented with FreeFem++ are presented.