CFD Online Discussion Forums - Access turbulence model in coded functionobjectlibs

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Access turbulence model in coded functionobjectlibs

Dear foamers,

I have been using function object libs now for a while to be able to do some extra coding at run time without modifying the solver.

Now I want to create a code snipped which calculates the RMS value of the solution matrix being solved, so you can access the accuracy of the solution.

My code snipped would look like

Code:

 



errorAnalysis

{

    functionObjectLibs ("libutilityFunctionObjects.so");

    type coded;

    redirectType average;

    outputControl timeStep;

    code

    #{

      const volVectorField&      U=mesh().lookupObject<volVectorField>("U");

      const surfaceScalarField& phi=mesh().lookupObject<surfaceScalarField>("phi");

      const volScalarField&      p=mesh().lookupObject<volScalarField>("p");







fvVectorMatrix residualMatrix

         (

                fvm::ddt(U)

            +  fvm::div(phi, U)  

            +  turbulence->divDevReff(U)

            +  fvc::grad(p)

         );



        Info << "RMS residualMatrix: " << Foam::sqrt(gSumMag(magSqr(residualMatrix.residual()))) << nl  ;





    #};

}

This piece of code works if I put it in the solver, but in the coded functionobject libs I do not know how to access the turbulence pointer using the lookupObject. Would somebode know how to access the divDevReff in code snipped dynamically linked at the case level ?

Regards

Eelco

As a work around in order to access the turbulence->divDevReff from the dynamically linked function object I found the following.

Code:

errorAnalysis

{

    functionObjectLibs ("libutilityFunctionObjects.so");

    type coded;

    redirectType average;

    outputControl timeStep;

    code

    #{



      const volVectorField&      U=mesh().lookupObject<volVectorField>("U");

      const surfaceScalarField&  phi=mesh().lookupObject<surfaceScalarField>("phi");

      const volScalarField&      p=mesh().lookupObject<volScalarField>("p");

      const volScalarField&      nuSgs=U.db().lookupObject<volScalarField>("nuSgs");

      const dictionary& transportProperties = U.db().lookupObject<IOdictionary>

      (

         "transportProperties"

      );

      const dimensionedScalar&   nu(transportProperties.lookup("nu"));



      fvVectorMatrix residualMatrix

         (

              fvm::ddt(U)

            + fvm::div(phi, U)

            - fvm::laplacian(nu+nuSgs, U) - fvc::div((nu+nuSgs)*dev(T(fvc::grad(U))))

            + fvc::grad(p)

         );



       Info << "RMS residualMatrix: " << Foam::sqrt(gSumMag(magSqr(residualMatrix.residual()))) << nl  ;

    #};

}

It works, but is rather ugly. I prefer to replace the line fvc::div((nu+nuSgs)*dev(T(fvc::grad(U)))) with turbulence-> value. Does anybody has a hint?

Hello

Is the 'type coded' option available in OF 1.7.1? I get an error: Unknown function type coded
Is there a way to implement it in OF 1.7.1?

Thanks!
ak

The coded functionObjects seem to be only available in OpenFOAM 2.0+

See this release notes:

http://www.cfd-online.com/Forums/ope...unction+object

Hi Eelcovv,

Did you ever have any more success trying to access the turbulence data from coded function objects? I was trying to do something similar, and found the obr() function. This returns a reference to the object registry, which lists the turbulence model, and can supposedly return a reference to it. However, I kept getting errors when I tried to get at the turbulence model through the lookupObject function, but kept getting errors (type incompressible::turbulenceModel not found, foundObject method not valid), and wasn't sure how to link in the required libraries.

Can anyone please advise how to access turbulenceModel in a coded functionObject?
obr() which is mentioned is the same as mesh() but it only has a reference to turbulence dictionary, not the object itself! I need to access epsilon of an LES simulation which cannot be found through lookupObject. I looked into the file and to calculate it directly I still need k which is the subgridscale kinetic energy in an LES simulation.

Quote:

Originally Posted by anishtain4 (Post 628567)

i am having the same problem. anyone has the solution???

thank you.