[Andy_ilek]

Hey,

I'm tring to model a 2D flow around a square. I used the following conditions:

- Solver: PisoFoam
- Turbulence Model: k-omega SST
- velocity uniform: 22m/s
- The square is 40m*40m (So i get really high Re-Number)


The input files are attached below. Does anybody already modelled a body with sharp edges and high Reynoldsnumber and has experience setting the boundary condition?

Is there something different than setting boundary conditions for an airfoil?

thanks already



/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / 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 (22 0 0);

boundaryField
{
inlet
{
type freestream;
freestreamValue $internalField;
}

outlet
{
type freestream;
freestreamValue $internalField;
}
upanddown
{
type freestream;
freestreamValue $internalField;
}
body
{
type fixedValue;
value uniform (0 0 0);
}

frontandback
{
type empty;
}
}

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

/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / 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 85796;

boundaryField
{
inlet
{
type freestreamPressure;
}

outlet
{
type freestreamPressure;
}

upanddown
{
type freestreamPressure;
}

body
{
type zeroGradient;
}

frontandback
{
type empty;
}
}

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

/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
location "0";
object k;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 2 -2 0 0 0 0];

internalField uniform 0.01;

boundaryField
{
inlet
{
type inletOutlet;
inletValue $internalField;
}

outlet
{
type inletOutlet;
inletValue $internalField;
}

upanddown
{
type inletOutlet;
inletValue $internalField;
}

body
{
type kqRWallFunction;
value uniform 0;
}

frontandback
{
type empty;
}
}

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


/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object omega;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 0 -1 0 0 0 0];

internalField uniform 100;

boundaryField
{
inlet
{
type inletOutlet;
inletValue $internalField;
}

outlet
{
type inletOutlet;
inletValue $internalField;
}

upanddown
{
type inletOutlet;
inletValue $internalField;
}

body
{
type omegaWallFunction;
value uniform 0; // es bleibt allerdings durch die WallFunction nicht 0 !
}

frontandback
{
type empty;
}
}

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

/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.1.1 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class volScalarField;
object nut;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions [0 2 -1 0 0 0 0];

internalField uniform 0.14;

boundaryField
{
inlet
{
type freestream;
freestreamValue $internalField;
}

outlet
{
type freestream;
freestreamValue $internalField;
}

upanddown
{
type freestream;
freestreamValue $internalField;
}

body
{
type nutkWallFunction;
value uniform 0;
}

frontandback
{
type empty;
}
}

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

[nimasam]

it seems OK for me , just some small questions:
1- did you check Mach number? is it incompressible flow (Mach < 0.3)?
2- you use incompressible solver pisoFoam, is there any reason you assign p = 85796 ? you could put it zero

3- if you are looking for steady state solution, then simpleFoam can be considered too