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Old   August 1, 2016, 10:24
Default Residual control
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Felix
Join Date: Sep 2015
Location: Hannover, Berlin
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Well i have a case, in which i will reduce the runtime.

I am using the interPhasechangeDyM Solver

I allredy have reduced the runtime from 100% to 33% with improving the pressure iteration speed.

My Problem is that im iteration the variable p_corr.

In that case I am using these specs below
Code:
    
"pcorr.*"
    {

        solver          GAMG;
        tolerance       1e-4;
        relTol          0;
        smoother        DICGaussSeidel;
        cacheAgglomeration no;
        nCellsInCoarsestLevel 20;
        agglomerator    faceAreaPair;
        mergeLevels     1;

    }
...
PIMPLE
{
    momentumPredictor          no;
    correctPhi          yes;
    nOuterCorrectors    7;
    nCorrectors         1;
    nNonOrthogonalCorrectors 10;
    residualControl
    {
        p_rgh
        {
            tolerance 1e-7;
            relTol 0;
            absTol 0;
        }
    }
}
in the first Timestep im getting this
Code:
Execution time for mesh.update() = 2.69 s
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 7.030918589e-05, No Iterations 15
GAMG:  Solving for pcorr, Initial residual = 0.1618379063, Final residual = 9.09515451e-05, No Iterations 5
GAMG:  Solving for pcorr, Initial residual = 0.03177132081, Final residual = 3.050995536e-05, No Iterations 5
GAMG:  Solving for pcorr, Initial residual = 0.01138752385, Final residual = 5.915332199e-05, No Iterations 3
GAMG:  Solving for pcorr, Initial residual = 0.004623339973, Final residual = 4.032533298e-05, No Iterations 3
GAMG:  Solving for pcorr, Initial residual = 0.002091591789, Final residual = 2.678131328e-05, No Iterations 2
GAMG:  Solving for pcorr, Initial residual = 0.000935694126, Final residual = 6.876109491e-05, No Iterations 1
GAMG:  Solving for pcorr, Initial residual = 0.0004440894954, Final residual = 3.892454402e-05, No Iterations 1
GAMG:  Solving for pcorr, Initial residual = 0.0002179582446, Final residual = 2.564707496e-05, No Iterations 1
GAMG:  Solving for pcorr, Initial residual = 0.0001126573963, Final residual = 1.363380582e-05, No Iterations 1
GAMG:  Solving for pcorr, Initial residual = 5.807458978e-05, Final residual = 5.807458978e-05, No Iterations 0
time step continuity errors : sum local = 3.835607192e-09, global = 8.465794602e-12, cumulative = 8.465794602e-12
but in the most timesteps after this im getting this
Code:
Execution time for mesh.update() = 2.72 s
GAMG:  Solving for pcorr, Initial residual = 1, Final residual = 9.089048299e-05, No Iterations 28
GAMG:  Solving for pcorr, Initial residual = 0.0002686212536, Final residual = 4.119209357e-05, No Iterations 1
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
GAMG:  Solving for pcorr, Initial residual = 7.742703334e-05, Final residual = 7.742703334e-05, No Iterations 0
time step continuity errors : sum local = 1.8005001e-05, global = 4.661703486e-06, cumulative = 4.661711952e-06
Is there any possibility to set a convergence criteria that is only responssible for p_corr and can reduce my -Zero Iterations-?
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Old   August 2, 2016, 08:04
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Felix
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What i exactly mean is the following:

is there any residual criteria for the nNonOrthogonalCorrectors?

I dont wanna do additional iterations loops, when the nNonOrthogonalCorrectors allready have reached the residuals.
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