Well-Posedness and Qualitative Behaviour of a Two-phase Navier-Stokes/Mullins-Sekerka system with boundary contact

Abstract: We consider a coupled two-phase Navier-Stokes/Mullins-Sekerka system describing the motion of two immiscible, incompressible fluids inside a bounded container. The moving interface separating the liquids meets the boundary of the container at a constant ninety degree angle. This common interface is unknown and has to be determined as a part of the problem. We show well-posedness and investigate the long-time behaviour of solutions starting close to certain equilibria. We prove that for equal densities these solutions exist globally in time, are stable, and converge to an equilibrium solution at an exponential rate.