Towards a Robust Multigrid Algorithm with Mach Number and Grid Independent Convergence
نویسنده
چکیده
A semi-coarsened multigrid algorithm with a point block Jacobi smoother for the Euler equations is presented which produces convergences rates independent of grid size for moderate subsonic Mach numbers. By incorporation of local precondition-ing, the performance of the multigrid algorithm can be made largely independent of grid size and Mach number over a range of ow conditions from nearly incompressible to transonic ows including internal and external ows.
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A Robust Multigrid Algorithm for the EulerEquations with Local Preconditioningand Semi-coarsening
A semi-coarsened multigrid algorithm with a point block Jacobi, multi-stage smoother for second-order upwind discretizations of the two-dimensional Euler equations which produces convergence rates independent of grid size for moderate subsonic Mach numbers is presented. By modification of this base algorithm to include local preconditioning for low Mach number flows, the convergence becomes lar...
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