flow over cylinder
1 Attachment(s)
Hi
i am working on flow past cylinder with Re=0 ,i attached geometry .there are no require set pressure boundary at AB and BC ,how can i implement it in 0/p?i set it as below but no working fine.please help /** C++ **\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.2.2   \\ / A nd  Web: www.OpenFOAM.org   \\/ M anipulation   \**/ FoamFile { version 2.0; format ascii; class volScalarField; object p; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 2 0 0 0 0]; internalField uniform 1; boundaryField { left { type symmetryPlane; } right { type fixedValue; value uniform 0; } down { type symmetryPlane; } up { type zeroGradient; } cylinder { type zeroGradient; } frontAndBack { type empty; } } /** C++ **\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.2.2   \\ / A nd  Web: www.OpenFOAM.org   \\/ M anipulation   \**/ FoamFile { version 2.0; format ascii; class volVectorField; object U; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 1 0 0 0 0]; internalField uniform (0 0 0); boundaryField { left { type symmetryPlane; } right { type fixedValue; value uniform (0 1 0); } down { type symmetryPlane; } up { type fixedValue; value uniform (0 1 0); } cylinder { type fixedValue; value uniform (0 0 0); } frontAndBack { type empty; } } /** C++ **\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.2.2   \\ / A nd  Web: www.OpenFOAM.org   \\/ M anipulation   \**/ FoamFile { version 2.0; format ascii; class dictionary; location "system"; object fvSolution; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // solvers { p { solver GAMG; tolerance 1e6; relTol 0; smoother GaussSeidel; nPreSweeps 2; nPostSweeps 2; cacheAgglomeration on; agglomerator faceAreaPair; nCellsInCoarsestLevel 10; mergeLevels 1; } U { solver smoothSolver; tolerance 1e6; relTol 0; smoother GaussSeidel; } } SIMPLE { nNonOrthogonalCorrectors 0; pRefPoint (2,0,0); pRefCell 0; residualControl { p 1e3; U 1e4; } } relaxationFactors { fields { p 0.3; } equations { U 0.7; } } 
Hi,
I am not sure what you mean by Re=0. So there is no flow at all? Can please provide an error message or what exactly is not working? 
On the right hand side you have a symmetry wall, yet you want a flow perpendicular to it? I do not think thats physically possible. Correct me if I am wrong, by in a symmetry plane the massflow should be 0 and thus the stream lines need to parallel to the surface, otherwise you have a line with mass constantly flowing in from both sides. Where is the fluid supposed to go without removing mass or compressing it to infinity?

2 Attachment(s)
Dear
there was some mistake in the picture,i changed it. the flow is nonnewtonnian (creeping flow like foams , filled polymer solution ) therefore re<<1, i attached the governing equations .the problem considered with two planes of symmetry, hence one quater of the domain is used,also i attached the all domain. Thanks 
Hi all,
Finally it is exact that one here: http://www.holzmanncfd.de/index.php...gelumstroemung But in your case it is a nonnewtonian flow. Based on the tensors and fluid behaviors, maybe you are allowed to simplify the deviatoric stress tensor to get a Poisson equation but maybe it is not possible. Anyway (: 
1 Attachment(s)
Dear Tobi
I attach the domain ,I dont want to apply pressure boundary condition at AB(up) and BC (right) ,how can i do it in the codes? object p; boundaryField { left { type symmetryPlane; } right { ?????????????what should i write??? } up { ?????????????what should i write??? } . ... 
First guess,
PS: I am not sure if you can simplify the case in that way. It should be wrong if I think about it. You should have 2 symmetryPlanes but could it be that you have 3. ? 
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