[rushs777]

Hi,

I am a new user to Open Foam, and I am trying to understand the code in the UEqn.H file in simpleFoam. On line 9, as part of establishing the left-hand side of the U equation, there is the command "+ turbulence->divDevReff(U)". My understand is that the implementation of divDevReff(U) will be selected by the turbulence model choice made in constant/TurbulenceProperties. Several sources (http://openfoamwiki.net/index.php/Bu...DevReff.28U.29, http://www.cfdsupport.com/OpenFOAM-T...t/node209.html), seemed to support this. However, whenever I look in any of the files I have for Open Foam v3.0, I can find no function definition in any of the turbulence models. In fact, the only thing I can find in regards to divDevReff(U) is a series of virtual functions defined in IncompressibleTurbulenceModel.C (http://www.openfoam.com/documentatio...96_source.html). Seeing as how most of the solvers have a line like this, plus the tutorials were working, there is just something about this I'm not getting. Would anyone mind sharing with me how this works, and where the definitions are for divDevReff(U) in the different turbulence classes? Thanks!

[ChGr]

Hey,

the definition of divDevReff(U) can be found in the file linearViscousStress.

https://github.com/OpenFOAM/OpenFOAM...iscousStress.C

[rushs777]

Thanks for the reply, but that is actually divDevRhoReff, and I am looking for divDevReff. Do you know where that is located?

[ChGr]

check here:

https://github.com/OpenFOAM/OpenFOAM...bulenceModel.C

[kaifu]

In OF 5.x
incompressible::turbulenceModel is defied as

typedef IncompressibleTurbulenceModel<transportModel> turbulenceModel;

the above class is inherit form class template TurbulenceModel

template<class TransportModel>
class IncompressibleTurbulenceModel
:
    public TurbulenceModel
    <
        geometricOneField,
        geometricOneField,
        incompressibleTurbulenceModel,
        TransportModel
    >

where the class template
TurbulenceModel
<
geometricOneField,
geometricOneField,
incompressibleTurbulenceModel,
TransportModel
>
is inherit from class incompressibleTurbulenceModel, as

template
<
    class Alpha,
    class Rho,
    class BasicTurbulenceModel,
    class TransportModel
>
class TurbulenceModel
:
    public BasicTurbulenceModel

class incompressibleTurbulenceModel is inherit from class turbulenceModel as

class incompressibleTurbulenceModel
:
    public turbulenceModel

in solver simpleFoam if we seclect kEpsilon as turbulenceModel
the function divDevRhoReff is interpretted in the following way

template<class BasicTurbulenceModel>
class kEpsilon
:
    public eddyViscosity<RASModel<BasicTurbulenceModel>>

template<class BasicTurbulenceModel>
class eddyViscosity
:
    public linearViscousStress<BasicTurbulenceModel>

template<class BasicTurbulenceModel>
Foam::tmp<Foam::fvVectorMatrix>
Foam::linearViscousStress<BasicTurbulenceModel>::divDevRhoReff
(
    volVectorField& U
) const
{
    return
    (
      - fvc::div((this->alpha_*this->rho_*this->nuEff())*dev2(T(fvc::grad(U))))
      - fvm::laplacian(this->alpha_*this->rho_*this->nuEff(), U)
    );
}