CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   OpenFOAM Running, Solving & CFD (http://www.cfd-online.com/Forums/openfoam-solving/)
-   -   Enclose equation in simplefoamget another result (http://www.cfd-online.com/Forums/openfoam-solving/57835-enclose-equation-simplefoamget-another-result.html)

booz March 9, 2009 06:08

Hi OpenFoam experts, is it
 
Hi OpenFoam experts,

is it a difference for openFoam or get another results, if for example I write in simpleFoam-case solver
...
tmp<fvvectormatrix> UEqn
(
fvm::div(phi, U)
+ turbulence->divR(U)
+ fvc::grad(p)
);

UEqn().relax();
solve(UEqn() == 0);// change
...

instead of
...
tmp<fvvectormatrix> UEqn
(
fvm::div(phi, U)
+ turbulence->divR(U)
);

UEqn().relax();

solve(UEqn() == -fvc::grad(p));
...

I suppose i get another result, if i view the flows in paraFoam.

Regards,
Khaled

grtabor March 9, 2009 06:15

Actually what you have done he
 
Actually what you have done here is to change the SIMPLE algorithm very fundamentally. SIMPLE (and PISO) split the discretisation of the momentum equation into pressure and everything else; what you have done is to lump them all in together.

Gavin

booz March 9, 2009 06:26

Hi Gavin, that is it is a d
 
Hi Gavin,

that is it is a disadvantage with regards to the convergence?

Regards,
Khaled


All times are GMT -4. The time now is 22:32.