[aan555]

Hello OpenFoamers,

Iam calculating a 3D unstructed mesh. The solver runs through, if I calculate steady state. Now i´ve tried to switch it to Piso and changed the ControlDict file like below:

*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.6 |
| \\ / A nd | Web: http://www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
object controlDict;
}

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
application pisoFoam;

startFrom startTime;

startTime 0;

stopAt endTime;

deltaT 0.005;

endTime 300;

writeControl timeStep;

writeInterval 100;

purgeWrite 1;

writeFormat ascii;

writePrecision 6;

writeCompression uncompressed;

timeFormat general;

timePrecision 6;

runTimeModifiable yes;

adjustTimeStep yes;

maxCo 0.2;

maxDeltaT 1;

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

One Question is:
1) Do I need a moving wall if my contolvolume is already initialised with a velocity?
and i get with piso now the following error message:

Fatal error: face xy area does not match neighbour by 200% -- possible face ordering problem.

i tried to find a solution here, but the threads didnt help me

2) Has someone a hint what the problem could be?

Iam pleased about every opinion and thx for now!

Miriam

[nimasam]

it doesn't seem about solver problem! it is about mesh!
do you use the same mesh with other solvers????
could you please upload your mesh

[aan555]

i use exactly the same mesh, i used before, i already get a solution with this mesh, but with steady state.
what file do you want to see, if you wanna see the mesh?

[darai]

To post the mesh you should probably zip the whole constant/polyMesh subdirectory... if it isn't too large.

[aan555]

sorry, its not possible to upload my mesh. Could you please give me some hints youre looking especially at, when youre using the PISO Solver?

Thanks!

[Chris Lucas]

Hi,

could you upload the checkMesh result. What steady state and what transient solver do you use. Could you upload the fvSolution and fvScheme files for both cases

Best Regards,
Christian

[wiedangel]

Originally Posted by aan555

Fatal error: face xy area does not match neighbour by 200% -- possible face ordering problem.

i think the problem with "Fatal error: face xy area does not match neighbour by 200% -- possible face ordering problem." comes from the cyclic boundary conditions being applied, if it is the case just increase the tolerance in the file constant/polymesh/boundary where your cyclic patch is. I hope it will help

Which time scheme did you use with piso?

[aan555]

I used Euler for the time scheme.
You were right, the problem were a mesh with a bad resolution at a cyclic patch. Well, i solved that with a new mesh, but now i got a new error message, which i dont understand:

incorrect first token, expected '(', found on line x the punctation token ')'
From function operator>>(Istream&, List<T>&)
in file .../ListIO.C

i just put it in here, maybe some know where that come from?

Thx!

[wiedangel]

Originally Posted by aan555

I used Euler for the time scheme.
You were right, the problem were a mesh with a bad resolution at a cyclic patch. Well, i solved that with a new mesh, but now i got a new error message, which i dont understand:

incorrect first token, expected '(', found on line x the punctation token ')'
From function operator>>(Istream&, List<T>&)
in file .../ListIO.C

i just put it in here, maybe some know where that come from?

Thx!

when do you get this error? when you execute blockMesh or the solver?

[aan555]

when i excecute the solver