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Low pressure result in low velocity region for RNG-ke?

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Old   July 14, 2011, 20:48
Default Low pressure result in low velocity region for RNG-ke?
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I have ran a SimpleFOAM RAS -RNG- K-e model of a ball vale at a small % opening position, as an axi symmetric model.
At the moment I have using PCG with a preconditioner of GAMG for the pressure calculations in fv schemes:
solver PCG;
preconditioner GAMG;
tolerance 1e-7;
relTol 0.1;
smoother GaussSeidel;
nPreSweeps 0;
nPostSweeps 2;
cacheAgglomeration on;
agglomerator faceAreaPair;
nCellsInCoarsestLevel 10;
mergeLevels 1;
tolerance 1e-06;
relTol 0.01;
maxIter 100;

solver PBiCG;
preconditioner DILU;
tolerance 1e-05;
relTol 0.1;

for K U and epsilon

My relaxation factors are:
p 0.7;
U 0.2;
k 0.5;
epsilon 0.5;

My result has an extremely low pressure region in area of low velocity. I feel as though this is not correct and am not sure what to do to optimize the model and get a better result. I have tried adjusting delta T and write time in controldict. I can get pressure residuals to converge but still have the same result
Any Ideas?
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