[Kina]

Hey guys,
I have a problem that is rather about physical understanding as I don't know which BCs to set. I am trying to implement a velocity-inlet in a compressible case ran with rhoPimpleFoam. I need this v-inlet because I want to create velocity defects for wake induced transition research on compressible flow. However, I struggle to determine the right BCs for that case.

I am operating at Ma = 0.65 and Re = 150,000 or at least I am trying to.
First thing for the v-Inlet was v = Ma * a with a = 331m/s which gives me the inlet velocity.

My BCs look like this:

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

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

internalField   uniform $U_internal;

boundaryField
{
    inlet
    {
          type    fixedValue;
          value uniform (216 0 0);
    }
    
    outlet
    {
        type            zeroGradient;
    }
    periodic-stator-top
    {
        type            cyclicAMI;
    }
    periodic-stator-bot
    {
        type            cyclicAMI;
    }
    wall-stator
    {
        type            fixedValue;
        value            uniform (0 0 0);
    }
    empty-stator
    {
        type            empty;
    }
}


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

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

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

internalField   uniform $p_outlet;

boundaryField
{
    inlet
    {
        type            zeroGradient;
    }
    outlet
    {
        type            fixedValue;
        value            $internalField;
    }
    periodic-stator-top
    {
        type            cyclicAMI;
    }
    periodic-stator-bot
    {
        type            cyclicAMI;
    }
    wall-stator
    {
        type            fixedFluxPressure;
        value           uniform 0;
    }
    empty-stator
    {
        type            empty;
    }
}

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

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

dimensions      [0 0 0 1 0 0 0];

internalField   uniform $T_outlet;

boundaryField
{
    inlet
    {
        type            totalTemperature;
        gamma            1.4;
        T0                $T_inlet;
        U               U;
        phi             phi;
        psi             thermo:psi;
    }
    outlet
    {
        type            inletOutlet;
        value           uniform $T_outlet;
        inletValue      uniform $T_outlet; //static outlet temp
    }
    periodic-stator-top
    {
        type            cyclicAMI;
    }
    periodic-stator-bot
    {
        type            cyclicAMI;
    }
    wall-stator
    {
        type            zeroGradient;
    }
    empty-stator
    {
        type            empty;
    }
}

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

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

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

internalField   uniform 0;

boundaryField
{
    inlet
    {
        type            calculated;
        value           $internalField;
    }
    outlet
    {
        type            calculated;
        value           $internalField;
    }
    periodic-stator-top
    {
        type            cyclicAMI;
    }
    periodic-stator-bot
    {
        type            cyclicAMI;
    }
    wall-stator
    {
        type            fixedValue;
        value           uniform 0;
    }
    empty-stator
    {
        type            empty;
    }
}


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

It'd be awesome if anyone could shed a bit of light on this. Didn't find any way to implement a velocity inlet into compressible flow. Also: How do I adjust the Reynolds Number? In compressible flow, it is affected by the rho but I don't know how I can pass the rho to the BCs initially.

Thanks and best
Alex

[Kina]

Did anyone experience such a problem so far? would be very helpful!

[lukasf]

Hi Kina,

what have you done so far? Were you able to solve your problem? What are your error messages?

I also want to use rhoPimpleFoam with a combination of the waveTransmissive and pressureInletOutletVelocity boundary conditions.

Lukas