Multigrid Solution of the Incompressible Navier-Stokes
                       Equations in General Coordinates

                           S. Zeng and P. Wesseling
             Department of Technical Mathematics and Informatics
                        Delft University of Technology
                                  Mekelweg 4
                                2628 CD Delft
                               The Netherlands

                                   Abstract

Galerkin coarse grid approximation (GCA) in multigrid methods is investigated
for the incompressible Navier-Stokes equations in general coordinates.  An
efficient algorithm performing GCA is presented.  The behavior of coarse grid
matrices is studied under GCA with different transfer operators.  For aquare
and L-shaped driven cavaty problems, the performance of the multigrid methods
using different combinations of transfer operators for the computation of
coarse grid matrices and of coarse grid correction is investigated.  Further
computations are carried out in general coordinates for a channel flow problem
with backward facing step in three dimensions.