A Coupled Multigrib Methodfor Nonconforming Finite Element Discretizations of the 2D-Stokes Equation

摘要

This paper investigates a multigrib method for the solution of the saddle point formulation of the discrete Stokes equation obtained with inf-sup stable nonconforming finite elements of lowest order. A smoother proposed by Braess and Sarazin(1997) is used and L~2-norm of the velocity with a rate independently of the level and linearly decreasing with increasing number of smoothing steps is proven Numerical testsconfirm the theoretically predicted results.