[giack]

Hi to all,I have a problem with an upwind div scheme

I set this scheme:
divSchemes
{
div(rho*phi,U) Gauss linearUpwindV cellLimited Gauss linear 1;
div(phi,alpha) Gauss vanLeer;
div(phirb,alpha) Gauss interfaceCompression;
}

the simulation is good but in my log file there is the following warming message:
--> FOAM Warning :
From function linearUpwindV(const fvMesh&, const surfaceScalarField& faceFlux, Istream&)
in file interpolation/surfaceInterpolation/schemes/linearUpwind/linearUpwindV.H at line 153
Reading "/home/giacomo/Scrivania/20x20x500UP/processor0/../system/fvSchemes::divSchemes::div(rho*phi,U)" at line 30
unexpected additional entries in stream.
Only the name of the gradient scheme in the 'gradSchemes' dictionary should be specified.

It have influence on simulation?
Another question: I would discretize all U terms with an upwind scheme. So i would choose an upwind scheme for the term grad(U) but I obtain an error message and the simulation don't start...How I can set an upwind scheme also for grad(U)

thank to all

[wyldckat]

Greetings giack,

This isn't my field of expertise, but the following line is clearly wrong:

div(rho*phi,U)  Gauss linearUpwindV cellLimited Gauss linear 1;

If I'm not mistaken, if should be something like:

div(rho*phi,U)  Gauss linearUpwind grad(U);

at least based on what I've seen in tutorials...

You can find more examples, by running:

find $FOAM_TUTORIALS -name "fvSchemes" | xargs grep "grad(U);"

If you want to change how "grad(U)" is done, should add the entry to the "gradSchemes" block:

gradSchemes
{
    default         Gauss linear;
    grad(U)        cellLimited Gauss linear 1;
}

Best regards,
Bruno

[giack]

thank you for your relpy.
I already tried your last advice but I have another error and simulation don't start. This is a very strange case.
Moreover I find that with the istruction
div(rho*phi,U) Gauss linearUpwindV cellLimited Gauss linear 1;
OF neglect the command and choose the default value for gradScheme required in the div term. So i use the following line:
div(rho*phi,U) Gauss linearUpwindV default;
I think that there aren't a lot of differences beetwen two gradSchene,it's true?

[Tushar@cfd]

Originally Posted by giack

thank you for your relpy.
I already tried your last advice but I have another error and simulation don't start. This is a very strange case.
Moreover I find that with the istruction
div(rho*phi,U) Gauss linearUpwindV cellLimited Gauss linear 1;
OF neglect the command and choose the default value for gradScheme required in the div term. So i use the following line:
div(rho*phi,U) Gauss linearUpwindV default;
I think that there aren't a lot of differences beetwen two gradSchene,it's true?

Are you able to solve your problem?
Try the scheme limitedLinear and do let us know about the results.

[giack]

Hi,
at this time I'm simulating two case: one with limetedLinearV 1 and the other with linearUpwindV Gauss linear. Simulations are not over yet but when they end I post my results.