[Mwill]

Hi Foamers,

I am a relatively new CFD user and I'm interested in setting up case termination for my transient simulation in my custom solver based on PISOfoam (essentially I have just added a scalar transport equation for psi after the PISO algorithm).
I'm interested in stopping the simulation after the residuals in U, p have reached their steady value and after psi has dropped below a residual threshold e.g. at around 100s in my residual plot https://imgur.com/a/ojKUKQV before reaching endTime prescribed.
I'm not sure if the oscillations in residuals are affecting this in anyway but the actual solution seems to be fine - the physical situation is a simple laminar scalar transport case in a simple parallel plate so I don't think there is anything strange going on.

I think the functionality I'm interested in is implemented in residualControl.I've tried using it inside the PISO brackets and just inside fvSolution but neither seems to work for the parameters I set.
It seems e.g. in documentation https://www.openfoam.com/documentati...rmination.html this only works for SIMPLE and PIMPLE solvers but not PISO. I want an automated termination since I will be doing parameter sweeps so need to save on computation once a sufficiently steady state has been reached but for later simulations I will be interested in transient effects which is why I am using PISO at the moment so switching to SIMPLE wouldn't work for me.

Thanks,
MW

Example fvSolution file below:

/*--------------------------------*- C++ -*----------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Version:  6
     \\/     M anipulation  |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "system";
    object      fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

solvers
{
    p
    {
        solver          GAMG;
        tolerance       1e-5;
        relTol          0.05;
        smoother        GaussSeidel;
        miniter         5;

    }

    pFinal
    {
        $p;
        smoother        DICGaussSeidel;
        tolerance       1e-5;
        relTol          0.0;
        minIter         5;
    }

    U
    {
        solver          smoothSolver;
        smoother        GaussSeidel;
        tolerance       1e-6;
        relTol          0;
        miniter         5;
    }

    psi
    {
        solver          smoothSolver;
        smoother        GaussSeidel;
        tolerance       1e-6;
        relTol          0;
        minIter         5;
    }
}

PISO
{
    nCorrectors     3;
    nNonOrthogonalCorrectors 0; 

}

residualControl
   {
       p 0.8e-5;
       U 0.8e-6;
       // Uz 1e-5;
       psi 0.8e-6;
   }

// ************************************************************************* //