[Jesus.M]

Hello OpenFOAM Community,

I am implementing the Artificial Compressibility method with dual-time stepping. I finished the code by adding a for loop in order to advance the solution in real time besides the pseudo-time stepping that this method uses. Therefore, I had to set also a counter for the real time and do several modifications to the code. I fixed some previous bugs that kept me from having a clean compilation. Once I had a clean compilation, I tried the code and it runs, but it does not print the solution for the specified time-step... Any suggestion of what it can be causing this problem?

Here's the code for more clarity.

int main(int argc, char *argv[])
{
   
        #include "postProcess.H"
        #include "addCheckCaseOptions.H"
        #include "setRootCaseLists.H"
        #include "createTime.H"
        #include "createMesh.H"
        #include "createControl.H"
        #include "createFields.H"
        #include "initContinuityErrs.H"
        #include "CourantNo.H"
        #include "readTimeControls.H"
        #include "setInitialDeltaT.H"


    scalar maxCoRealTime = runTime.controlDict().lookupOrDefault<scalar>("maxCoRealTime", 1.0);

    scalar realDeltaT = runTime.controlDict().lookupOrDefault<scalar>("realDeltaT", GREAT);
    
    scalar CoNumRealTime = 0.0;

    #include "CourantNoRealTime.H"

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

        Info<< "\nStarting time loop\n" << endl;

    //declaration Time Variables

        auto maxIterRealTime = runTime.controlDict().lookupOrDefault<scalar>("maxIterRealTime",1);
    auto maxIterPseudoTime = runTime.controlDict().lookupOrDefault<scalar>("maxIterPseudoTime",1);
        
    decltype(realDeltaT) timeTotalRealTime = 0.0;
    
    auto runRealTime = runTime.timeIndex();
    runRealTime = 0;

    //declaration of fluid properties

    decltype(U) Udt1 = U;
    decltype(U) Udt0 = U;
    
    
    //Real-time step
    for(auto i = decltype(maxIterRealTime){0}; i < maxIterRealTime; ++i)
    {

        ++runRealTime;
        #include "readRealTimeControls.H"
        #include "CourantNoRealTime.H"
        #include "setRealDeltaT.H"

        Udt0 = Udt1; // Updating U at real time. 

            

        //Pseudo-time step
        while (runTime.timeIndex() < maxIterPseudoTime)
        {

            ++runTime;

            //Time derivative

             auto dualDt = dimensionedScalar("dt_real", dimTime, realDeltaT);
                 Udt1    = U;
                 dt_ddt  = (Udt1 - Udt0) / dualDt;

            //CFL-based time-step

            #include "readTimeControls.H"
            #include "CourantNo.H"
                #include "setDeltaT.H"
                
        
                Info<< "Time = " << runTime.timeName() << nl << endl;
    
                //Continuity Equation

            phi = fvc::interpolate(U) & mesh.Sf();
        
            fvScalarMatrix pEqn
            (
              fvm::ddt(p) + beta * fvc::div(U)
            );

            //pEqn.setReference(pRefCell, pRefValue);

            pEqn.solve();
    
            #include "continuityErrs.H"

            p.correctBoundaryConditions();
    
            //Momentum Equation

                fvVectorMatrix UEqn
            (
              fvm::ddt(U) + fvm::div(phi,U) - fvm::laplacian(nu,U)
            );

            solve(UEqn == -fvc::grad(p) - dt_ddt);

        }
        
        runTime.printExecutionTime(Info);

        
        
        //Update Real time and reset pseudo-time
        
        timeTotalRealTime += realDeltaT;
       
        runTime.setTime(timeTotalRealTime, runRealTime);
            runTime.write();

        runTime.setTime(0.0, 0);
        
    }

    Info<< "End\n" << endl;

    return 0;
}

Thank you

[Jesus.M]

Hello OpenFOAM community,



I have figured out that the command runTime.write() does not work. However, I don't know the reason why.

Does anyone know why it can stop working?

[Jesus.M]

Hello,

I have found the problem. I will post the solution for anyone who encounters the same problem. The code ran fine. When you are doing dual-time stepping, you have to set the writeControl inside the controlDict file to timeStep.

Then, OpenFOAM will write every time-step in real time.