[heitorvitorc]

Hey guys,

I'm working on multiphase flow in porous media on microscale, using interFoam solver, and I need to validate the simulation with an experiment consisting on oil displacement in a microchannel. Thus, I prepared a 3D rectangle in gmsh and set it as filled with oil, in order to inject water.

It seems like the simulations are not returning physical sense, as the oil phase is not leaving the domain. I kindly ask for the community help to evaluate which are the proper boundary conditions for the alpha.water, p_rgh and U dictionaries, as I am new to such matters. Here are the assumptions:

Fully saturated channel;
Water is injected;
Oil leaves the channel as water moves into outlet.
Incompressible flow.

I appreciate any kind of help. Thanks in advance.

Best regards,
Vitor

FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      alpha.oil;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 0 0 0 0];


internalField   uniform 1;

boundaryField
{
    FrontAndBack
    {
        type            empty;
    }
    Inlet
    {
        type            fixedValue;
        //inletValue      uniform 0;
        value           uniform 1;
    }
    BottomWall
    {
        type            zeroGradient; // ignoring surface tension effects 
    }
    Outlet
    {
        type            inletOutlet;
        inletValue   uniform 0;
        value          uniform 0;
    }
    TopWall
    {
        type            zeroGradient; // ignoring surface tension effects 
    }
}

FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    object     

	
	
 p_rgh
;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 0;

boundaryField
{
    Inlet
    {
        type		fixedValue;
	value	uniform 10;
    }

    Outlet
    {
        type		fixedValue;
        value		uniform 0;
    }

    TopWall
    {
	type		zeroGradient;
    }
	
    BottomWall
    {
	type		zeroGradient;
    }

    FrontAndBack
    {
        type		empty;
    }

}

FoamFile
{
    version     2.0;
    format      binary;
    class       volVectorField;
    location    "0";
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0 0 0);

boundaryField
{
    FrontAndBack
    {
        type            empty;
    }
    Inlet
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }
    TopWall
    {
        type            noSlip;
    }
    Outlet
    {
        type            zeroGradient;
    }
    BottomWall
    {
        type            noSlip;
    }

}

[Stefanie.S.W.]

Hello Vitor,



did you try a fixed velocity inlet and a pressure outlet?

I think that those are quite easy BCs to begin with and have a 1st test run.

Maybe a fixed value inlet BC will work for you. It is used in the nozzleFlow tutorial. (interFoam les)


u_inlet

{

type fixedValue;
value uniform (x y z);
}
u_outlet
{
type zeroGradient;
}


prgh_inlet

{

type zeroGradient; }
prgh_outlet
{
type fixedValue;
value uniform 0;

}
Maybe a massFlowRate inlet would also work? (as in the angledDuct tutorial?)


Best,
Stefanie

[Rohitsingh]

Originally Posted by heitorvitorc

Hey guys,

I'm working on multiphase flow in porous media on microscale, using interFoam solver, and I need to validate the simulation with an experiment consisting on oil displacement in a microchannel. Thus, I prepared a 3D rectangle in gmsh and set it as filled with oil, in order to inject water.

It seems like the simulations are not returning physical sense, as the oil phase is not leaving the domain. I kindly ask for the community help to evaluate which are the proper boundary conditions for the alpha.water, p_rgh and U dictionaries, as I am new to such matters. Here are the assumptions:

Fully saturated channel;
Water is injected;
Oil leaves the channel as water moves into outlet.
Incompressible flow.

I appreciate any kind of help. Thanks in advance.

Best regards,
Vitor

FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      alpha.oil;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 0 0 0 0];


internalField   uniform 1;

boundaryField
{
    FrontAndBack
    {
        type            empty;
    }
    Inlet
    {
        type            fixedValue;
        //inletValue      uniform 0;
        value           uniform 1;
    }
    BottomWall
    {
        type            zeroGradient; // ignoring surface tension effects 
    }
    Outlet
    {
        type            inletOutlet;
        inletValue   uniform 0;
        value          uniform 0;
    }
    TopWall
    {
        type            zeroGradient; // ignoring surface tension effects 
    }
}

FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    object     

	
	
 p_rgh
;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 0;

boundaryField
{
    Inlet
    {
        type        fixedValue;
    value    uniform 10;
    }

    Outlet
    {
        type        fixedValue;
        value        uniform 0;
    }

    TopWall
    {
    type        zeroGradient;
    }
    
    BottomWall
    {
    type        zeroGradient;
    }

    FrontAndBack
    {
        type        empty;
    }

}

FoamFile
{
    version     2.0;
    format      binary;
    class       volVectorField;
    location    "0";
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0 0 0);

boundaryField
{
    FrontAndBack
    {
        type            empty;
    }
    Inlet
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }
    TopWall
    {
        type            noSlip;
    }
    Outlet
    {
        type            zeroGradient;
    }
    BottomWall
    {
        type            noSlip;
    }

}

I am also having same problem, can you share the solution if you resolved your problem?