Using PETSc in structured c-grid for CFD and multigrid

[Lisandro Dalcin]

On 1/26/07, Berend van Wachem <berend at tfd.chalmers.se> wrote:
> Multigrid is certainly possible (I would reccomend through HYPRE,
> discussed on the mailinglist, although I still have problems with it), but
> the question is how efficient it will be for your CFD problem.

>I doubt any "automatic" multigrid algorithm (in Hypre or
> Petsc) would be able to capture this, but don't quote me on it - I am not
> 100% sure.

Indeed. In my recent experience trying to use BoomerAMG (with fully
coupled, implicit FEM SUPG/PSPG formulation for incompressible NS
eqs.), the results were quite disappointing. I am now trying to
implement preconditioners based on approximate the Schur complement on
the pressure. This decouples the full problem, but it need to solve an
advection-diffusion-reaction problem and Poisson problems (such that
multigrid can work well oin them) each time the preconditioner is
applied.

-- 
Lisandro Dalcín
---------------
Centro Internacional de Métodos Computacionales en Ingeniería (CIMEC)
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