Effect of Artificial Diffusion Schemes on Multigrid Convergence

The effect of artificial diffusion schemes on the convergence of an implicit method is investigated. A multigrid code using a symmetric limited positive scheme in conjunction with a lowerupper symmetric-Gauss-Seidel method is developed for viscous compressible flows. The present numerical method is shown to be an effective multigrid driver in three-dimensions. Despite its reasonably fast convergence, the present code requires low computational work per iteration. The symmetric limited positive scheme improves the convergence characteristics of the implicit method on a high cell aspect ratio grid. The numerical results compare well with available experimental data.