A FETI-DP formulation for two-dimensional stokes problem on nonmatching grids

Abstract

We consider a FETI-DP formulation of the Stokes problem with mortar methods. To solve the Stokes problem correctly and efficiently, redundant continuity constraints are introduced. Lagrange multipliers corresponding to the redundant constraints are treated as primal variables in the FETI-DP formulation. We propose a preconditioner for the FETI-DP operator and show that the condition number of the preconditioned FETI-DP operator is bounded by C Maxi-1,...,N {(1+log(Hi/hi))2 where Hi and hi are the subdomain size and the mesh size, respectively, and C is a constant independent of Hi and hi.