ON COUPLED PROBLEMS FOR VISCOUS-FLOW IN EXTERIOR DOMAINS

The use of the complete Navier-Stokes system in an unbounded domain is not always convenient in computations and, therefore, the Navier-Stok es problem is often truncated to a bounded domain. In this paper we si mulate the interaction between the Row in this domain and the exterior flow with the aid of a coupled problem. We propose in particular a li near approximation of the exterior Row (here the Stokes flow or potent ial Row) coupled with the interior Navier-Stokes problem via suitable transmission conditions on the artificial interface between the interi or and exterior domains. Our choice of the transmission conditions ens ures the existence of a solution of the coupled problem, also for larg e data.