[Bedotto]

Hello Foamers,

I've a problem with the laplacian operator in openFoam. Indeed in my solver I've written successfully in my file.C the following heat equation:
(
fvm::ddt(T)
+ fvm::div(phi, T)
- fvm::laplacian(DT, T)
)
However I would like to add the term corresponding to the subsgrid scale model, I mean the term Nu_t/Pr_t. Where Nu_t is the turbulent viscosity and Pr_t the turbulent prandtl. The equation I have to write under openFoam is now: dT/dt + d(T*Ui)/dxi = d [( Nu/Pr +Nu_t/Pr_t) * dT/dxi ]/dxi
where Nu_t is not a constant of course. I call Nu_t with the sentence sgsModel->nuSgs(). (Thanks again Santos!)
I've tried to write the new equation like:
(
fvm::ddt(T)
+ fvm::div(phi, T)
- fvm::laplacian(DT,T)
- (fvm::laplacian(sgsModel->nuSgs(),T)) *(1/0.6)
-( fvc::grad(T) & fvc::grad(sgsModel->nuSgs()) ) *1/0.6
);
where Pr_t=0.6.
The problem is I get an error when I try to compile. The error comes from this line: - (fvm::laplacian(sgsModel->nuSgs(),T)) *(1/0.6)
Indeed it says:

Nueff.C: In function âint main(int, char**)â:
Nueff.C:133: error: no match for âoperator*â in âFoam::fvm::laplacian(const Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> >&, Foam::GeometricField<Type, Foam::fvPatchField, Foam::volMesh>&) [with Type = double](((Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&)(& T))) * 1.66666666666666674068153497501043602824211120605e +0â
/home/bedotto/OpenFOAM/OpenFOAM-1.4.1/src/OpenFOAM/lnInclude/dimensionedTensor.H:77:

I've tried to write this line in other ways
(for instance: fvm::laplacian(sgsModel->nuSgs()) *(1/0.6)*T + fvm::laplacian(T)*(1/0.6)*sgsModel->nuSgs(), but it doesn't work)
I think I don't use correctly this operator, maybe someone could tell me more about how does work this operator, or is there something in the programmer's guide I've missed?

My regards

Quentin