Christian Michelsen Research AS

P.O. Box 3

5036 Fantoft, Norway

The Additive Correction Multigrid strategy [B. R. Hutchinson and G. D. Raithby, Num. Heat Tranfer, 9, pp 511-537, 1986] is shown to be identical to a cell-centred multigrid algorithm using both restriction and prolongation operators based on piecewise constant interpolation. It is demonstrated that the method therefore cannot be expected to give true multigrid performance (i.e. grid-independent rate of convergence) for diffusion dominated problems.

Contributed March 28, 1995.