[hester]

Hello,

I am wondering where the Boltzmann constant value is set in OpenFOAM. The variable k is defined under src/OpenFOAM/global/constants/fundamental/fundamentalConstants.C.
I expected to find the value set here too, like for the Avogadro constant. (Actually, NA is the only value set her.)

 defineDimensionedConstantWithDefault
 (
     physicoChemical::group,
     physicoChemical::NA,
     Foam::dimensionedScalar
     (
         "NA",
         dimensionSet(0, 0, 0, 0, -1),
         6.0221417930e+23
     ),
     constantphysicoChemicalNA,
     "NA"
 );

 defineDimensionedConstant
 (
     physicoChemical::group,
     physicoChemical::k,
     constantphysicoChemicalk,
     "k"
 );

I also tried the doxygen documentation, but it only leads to the turbulence k value or some integer k in the LISA atomization method.

If anyone can point me in the right direction, I would be very grateful.

Regards,
hester

[msaravia]

The Boltzman's constant is is taken as variable by fundamentalConstants.H. Actuallyit is defined at line 41 of file LISASMDCalcMethod2.H. Check https://cpp.openfoam.org/v5/fundamen...stants_8H.html.

[hester]

Hello msaravia,

thank you for your reply.
If you look at your mentioned source code, you will see that k in this file is not the Boltzmann constant but it is an integer used for iteration. This is the file the doxygen documentation will lead you to if your looking for physicoChemical::k (as mentioned in my initial post).

Regards,
hester

[hyFoam]

Hi Hester,


The Boltzmann constant value is given in $WM_PROJECT_DIR/etc/controlDict

DimensionedConstants
{
    unitSet             SI; // USCS

    SICoeffs
    {
        physicoChemical
        {
            mu              mu [1 0 0 0 0 0 0] 1.66054e-27;
            k               k [1 2 -2 -1 0 0 0] 1.38065e-23;
        }
    }
}

Thanks,


Vince

[hester]

Hi Vince,


this is exactly what I was looking for.
Thank you!


hester