[rdbisme]

Hello everyody,

I'm trying to run a case with cyclic boundary conditions for a two-fluid problem.

I need so to set a driving force inside the domain and for what I know I should do that using fvOptions.

I have few questions:

OF 3.0.1

momentumSource
{
    type            meanVelocityForce;
    active          yes;

    meanVelocityForceCoeffs
    {
        selectionMode   all;

        fieldNames      (U);
        Ubar            (0 5 0);
    }
}

• can I use it with twoPhaseEulerFoam?
• in fieldnames should I put U.air/U.particles (as from constant/phaseProperties) or U1/U2 as from the UEqns.H in the solver sources?
• should I define a momentum source for both phases?
• how do I understand if fvOptions settings have been received correctly from the solver? In the log I have

  Creating finite volume options from "constant/fvOptions"
  
  Selecting finite volume options model type meanVelocityForce
      Source: momentumSource
      - selecting all cells
      - selected 450000 cell(s) with volume 0.00010598
      Initial pressure gradient = 0

  whatever fieldNames I put.

Thanks for your help,

[avila.vc]

Hi Ruben! How are you?

So, regarding your questions:

I use scalarSemiImplicitSource to set a velocity field source with twoPhaseEulerFoam (OF 30x), but I had a brief look at meanVelocityForce code source (src/fvOptions) and based on that, I think:

can I use it with twoPhaseEulerFoam? yes

in fieldnames should I put U.air/U.particles (as from constant/phaseProperties) or U1/U2 as from the UEqns.H in the solver sources? only (U.air) or (U.particles)

should I define a momentum source for both phases? if you want, you can, according to the source code. I think you should try defining one momentum source for EACH phase, separately.

how do I understand if fvOptions settings have been received correctly from the solver? In the log I have.
this one is a bit tricky for me. You may run test cases (with/without the source and with different force values) to analise the results and see if they seem consistent (I think there may be a simpler way, but I cant think of none in the moment)

I hope I have helped you a bit.

Best regards,

[rdbisme]

Originally Posted by avila.vc

Hi Ruben! How are you?

So, regarding your questions:

I use scalarSemiImplicitSource to set a velocity field source with twoPhaseEulerFoam (OF 30x), but I had a brief look at meanVelocityForce code source (src/fvOptions) and based on that, I think:

can I use it with twoPhaseEulerFoam? yes

in fieldnames should I put U.air/U.particles (as from constant/phaseProperties) or U1/U2 as from the UEqns.H in the solver sources? only (U.air) or (U.particles)

should I define a momentum source for both phases? if you want, you can, according to the source code. I think you should try defining one momentum source for EACH phase, separately.

how do I understand if fvOptions settings have been received correctly from the solver? In the log I have.
this one is a bit tricky for me. You may run test cases (with/without the source and with different force values) to analise the results and see if they seem consistent (I think there may be a simpler way, but I cant think of none in the moment)

I hope I have helped you a bit.

Best regards,

Thanks vinicius for your kind help. I managed to run the simulation as you suggested (even if I'm not sure it's working as expected). I will still keep checking on that.

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  3.0.1                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "constant";
    object      fvOptions;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

momentumSource
{
    type            meanVelocityForce;
    active          yes;

    meanVelocityForceCoeffs
    {
        selectionMode   all;

        fieldNames      (U.air);
        Ubar            (0 1 0);
    }
}

momentumSource1
{
    type            meanVelocityForce;
    active          yes;

    meanVelocityForceCoeffs
    {
        selectionMode   all;

        fieldNames      (U.water);
        Ubar            (0 1 0);
    }
}



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