[sasanghomi]

Hi foamers ,

What is motionU file ?? I think it used for cases with dynamic mesh.....
My second question is about componentMixed type that used for the piston in the below motionU file..what is componentMixed type ??what is ref value and value fraction???

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM Extend Project: Open source CFD        |
|  \\    /   O peration     | Version:  1.6-ext                               |
|   \\  /    A nd           | Web:      www.extend-project.de                 |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       tetPointVectorField;
    location    "0";
    object      motionU;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0 0 0);

boundaryField
{
    piston
    {
        type            componentMixed;
        refValue        uniform (0 0 0);
        valueFraction   uniform (0 0 1);
    }
    liner
    {
        type            componentMixed;
        refValue        uniform (0 0 0);
        valueFraction   uniform (1 1 0);
    }
    cylinderHead
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    intakePort
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    presin
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    exhaustPort
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    presout
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    valveCurtainCyl1
    {
        type            componentMixed;
        refValue        uniform (0 0 0);
        valueFraction   uniform (1 1 0);
    }
    valve1
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    valve2
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    valveCurtainPort1
    {
        type            zeroGradient;
    }
    valveDetachCyl1
    {
        type            zeroGradient;
    }
    valveDetachPort1
    {
        type            zeroGradient;
    }
    valveCurtainCyl2
    {
        type            componentMixed;
        refValue        uniform (0 0 0);
        valueFraction   uniform (1 1 0);
    }
    valve3
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    valve4
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    valveCurtainPort2
    {
        type            zeroGradient;
    }
    valveDetachCyl2
    {
        type            zeroGradient;
    }
    valveDetachPort2
    {
        type            zeroGradient;
    }
    defaultFaces
    {
        type            empty;
    }
}


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

Thanks and best regards,
Sasan.

[sasanghomi]

I appreciate any help.....

[ngj]

Hi Sasan,

The motionU file is related to the laplaceFace-/laplaceCellDecomposition methods, which are only available in OF16-ext. In This file you specify the behaviour of/boundary conditions for the mesh motion.

With respect to the component mixed, then the refValue and valueFraction are specific information needed by this boundary condition. I made a quick search in the source code, however, I cannot figure out what it is doing/which class it is derived from.

Good luck,

Niels

[sasanghomi]

Hi Niels ,
thank you very much.
Sasan.

[sasanghomi]

Hi Niels ,

Can you explain when I should use componentMixed and in this type which direction should be 1 and which one should be 0 ???(for example uniform (1 1 0) )
Actually the motionU file that I attached above is related a 2D engine simulation and I changed the geometry and I created a 3D engine and I want to know what are the boundary conditions in motionU that I must change them?

Thanks and best regards,
Sasan.