Analysis of a multigrid strokes solver

Model-problem analysis or local-mode analysis is used to investigate the two-level convergence rates for multigrid Strokes solvers. The solvers are based on the discretization on the staggered grid and the distributive relaxation of the continuity equation. The influence of the grid geometry is analyzed by also considering the Poisson equation on the semistaggered grid. Various grid transfer operators are compared. For an isotropic (h"x=h"y discretization, simple tranfer operators are sufficient to obtain optimal rates, but not in the anisotropic case. The theoretical results are compared with observed multigrid convergence rates.