We consider the equations of Navier-Stokes modeling viscous fluid flow past a moving or rotating obstacle in R d subject to a prescribed velocity condition at infinity. In contrast to previously known results, where the prescribed velocity vector is assumed to be parallel to the axis of rotation, in this paper we are interested in a general outflow velocity. In order to use L p -techniques we introduce a new coordinate system, in which we obtain a non-autonomous partial differential equation with an unbounded drift term. We prove that the linearized problem in R d is solved by an evolution system on L p σ (R d ) for 1 < p < ∞. For this we use results about time-dependent Ornstein-Uhlenbeck operators. Finally, we prove, for p ≥ d and initial data u 0 ∈ L p σ (R d ), the existence of a unique mild solution to the full Navier-Stokes system. (2000). Primary 35Q30; Secondary 76D03, 76D05.
Mathematics Subject Classification