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ziemowitzima April 5, 2010 13:43

GAMG on GPU for OpenFoam
Dear All,

Recently our working group developed linear iterative solvers on GPU (CUDA). We did PCG and BIGSTAB. We linked our library with OpenFoam.
To see more details please visit:

Now we want to make GAMG solver on GPU.
Does anyone of you know what exactly GAMG algorithm is used in OF ? Or where to find some information about GAMG ?

lth April 26, 2010 18:02

I've used GAMG to speed up three dimensional computations. It is a multigrid approach which sweep across a course number of points and then a dense number of points. To apply, go into the FVsolution folder and code the variable(s) like this Pressure variable for example.

To learn more about it... check out Gilbert Strang's CFD text. -Lori

p PCG //pressure
preconditioner GAMG
tolerance 1e-6;
relTol 0;
nVcycles 2;
smoother GaussSeidel;
nPreSweeps 0;
nPostSweeps 2;
nFinestSweeps 2;
cacheAgglomeration on;
nCellsInCoarsestLevel 20;
agglomerator faceAreaPair;
mergeLevels 1;

tolerance 1e-6;
relTol 0;
maxIter 20;

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