[sreehahaha]

Dear Foamers,

I have to define a surfaceScalarField in my code on-the-fly at each time-step for my system. In createFields.H, I do:

surfaceScalarField stochHfx
(
    IOobject
    (
        "stochHfx",
        runTime.timeName(),
        mesh,
        IOobject::NO_READ,
        IOobject::AUTO_WRITE
    ),
    mesh,
    dimensionedScalar("stochHfx", dimPower, scalar(0))
);

In the main solver.C file, I give values to stochHfx like

forAll(stochHfx,facei) // loop over all internal faces
{
	stochHfx[facei]=rnumq.scalarNormal(); //a random number
}

1. Now, I have to give random values to the boundary faces. How can I do it?

2. Mostly, I use a cubic domain with cyclicBC in all directinos. So, I have to make the values of stochHfx on the left patch the same as that on the right patch. How can I do that?

Any suggestion would be appreciated. I've been spending quite a long time on this, sadly.

Thanks,
S

[alundilong]

Originally Posted by sreehahaha

Dear Foamers,

I have to define a surfaceScalarField in my code on-the-fly at each time-step for my system. In createFields.H, I do:

surfaceScalarField stochHfx
(
    IOobject
    (
        "stochHfx",
        runTime.timeName(),
        mesh,
        IOobject::NO_READ,
        IOobject::AUTO_WRITE
    ),
    mesh,
    dimensionedScalar("stochHfx", dimPower, scalar(0))
);

In the main solver.C file, I give values to stochHfx like

forAll(stochHfx,facei) // loop over all internal faces
{
	stochHfx[facei]=rnumq.scalarNormal(); //a random number
}

1. Now, I have to give random values to the boundary faces. How can I do it?

2. Mostly, I use a cubic domain with cyclicBC in all directinos. So, I have to make the values of stochHfx on the left patch the same as that on the right patch. How can I do that?

Any suggestion would be appreciated. I've been spending quite a long time on this, sadly.

Thanks,
S

following is the general idea of how, hope it helps.

1. use Random object, such as Random rndGen(215444), then use this object to generate random numbers.
2. to access boundary faces of field alphaf(lets say)

//- loop all boundaryField of alphaf field
//- apply user-defined operation on each face
forAll(alphaf.boundaryField(), patchi)
{
fvsPatchScalarField& palphaf = alphaf.ref().boundaryFieldRef()[patchi];

forAll(palphaf, facei)
{
palphaf[facei] = rndGen.scalar01();
}
}

3. if you want to applied this a specific boundary, you can set it apart by its name.

palphaf.patch().name() should return the name of the boundary.

[sreehahaha]

Hi Alundilong,

Thanks a lot for the suggestion; very helpful. I think I got the idea.

Cheers,
S