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convergence check implemented in OF-1.6.x

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Old   May 31, 2010, 09:04
Default convergence check implemented in OF-1.6.x
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I use simpleFoam for hydrodynamic cases (external flow). I read here that convergence check has been implemented. Please, can anyone explain how to use it? I'd like to stop the solving process when convergence criterion is satisfied. What are the appropriate criteria for my case? I can't find any suggestion in the forum.
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Old   May 31, 2010, 09:59
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Cedric Van Holsbeke
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Just set a value for convergenceCriterion in the subdictionary SIMPLE of your fvSolution file, for example 1e-3 or 1e-5.
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Old   May 31, 2010, 10:37
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Sorry, it's not enough for me. I don't know or understand the syntax of the code lines (and where have i put them?) to check convergence. I need just an example, is something like
Code:
SIMPLE
{
    nNonOrthogonalCorrectors 0;
    convergenceCriterion 1e-5
}
in fvSolution?
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Old   May 31, 2010, 10:41
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Cedric Van Holsbeke
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Indeed, you are correct. Just put a semicolon behind the value:

Code:
SIMPLE
{
    nNonOrthogonalCorrectors 0;
    convergenceCriterion 1e-5;
}
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Old   May 31, 2010, 10:45
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You're right, I was absent-minded. Thank you, I'm going to test that.
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Old   June 3, 2010, 08:35
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I included in fvSolution
Code:
SIMPLE
{
    nNonOrthogonalCorrectors 0;
    convergenceCriterion 1e-5;
}
but I think simpleFoam made 1000 iterations with no convergences check:
Code:
smoothSolver:  Solving for Ux, Initial residual = 1.39053e-08, Final residual = 6.56736e-09, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 1.21505e-08, Final residual = 5.93553e-09, No Iterations 1
smoothSolver:  Solving for Uz, Initial residual = 2.05638e-08, Final residual = 9.82093e-09, No Iterations 1
GAMG:  Solving for p, Initial residual = 9.89818e-08, Final residual = 9.89818e-08, No Iterations 0
time step continuity errors : sum local = 5.09515e-08, global = -3.38207e-11, cumulative = 0.00191433
smoothSolver:  Solving for omega, Initial residual = 9.20253e-09, Final residual = 9.20253e-09, No Iterations 0
smoothSolver:  Solving for k, Initial residual = 9.94271e-09, Final residual = 9.94271e-09, No Iterations 0
ExecutionTime = 19135.6 s  ClockTime = 19607 s
What's the problem?
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