CFD Online Discussion Forums - IOobject returns constant value

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IOobject returns constant value

Hi,

I am trying to create a new IOobject (Reynoldsnumber). Therefore I have added the following lines in my createFields.H and compiled it without errors. Unfortunately only a const value is returned (for Re and nu):

Code:

volScalarField nu

    (

    IOobject

        (

            "nu",

            runTime.timeName(),

            mesh,

            IOobject::NO_READ,

            IOobject::AUTO_WRITE

        ),

         thermo.mu()/rho

     );





volScalarField L

(

    IOobject

    (

        "L",

        runTime.timeName(),

        mesh,

        IOobject::NO_READ,

        IOobject::AUTO_WRITE

    ),

    mesh,dimensionedScalar("L", dimensionSet(0,1,0,0,0,0,0),1 )

);



    volScalarField Re

    (

    IOobject

        (

            "Re",

            runTime.timeName(),

            mesh,

            IOobject::NO_READ,

            IOobject::AUTO_WRITE

           

        ),

         mag(U)*0.00095*L/nu

     );

Any idea what I am doing wrong?

Hi,

You need to update such volScalarFields in the time loop. Otherwise, they will always take the initial values defined in createFields.H.

Thank you very much, it seems to work now!

As you said, I have added the lines in the time loop of my solver:

Code:

nu = thermo.mu()/rho;

L = dimensionedScalar("L", dimensionSet(0,1,0,0,0,0,0),1 );

Re = mag(U)*0.00095*L/nu;