Finite element methods for the Stokes system in three-dimensional exterior domains (Q2785660)

The article treats the question of how to numerically solve the Dirichlet problem for the Stokes system in the exterior of a three-dimensional bounded Lipschitz domain. At the first step, the solution is approximated by functions solving the Stokes system in a truncated domain and satisfying a suitable artificial boundary condition on the outer boundary of this truncated domain. At the second step, this new problem is approximately solved in finite element spaces related to a graded mesh. The difference between this finite element approximation and the exact solution of the exterior Stokes problem is estimated in the norm of suitable unweighted \(L^2\)-Sobolev spaces.