[alimea]

Hi
I'm a new user in OpenFoam.
plz tell me about what these lines of "creatFields.H" files do:

volScalarField T
(
IOobject //What is it?
(
"omega",
runTime.timeName(),
mesh,
IOobject::MUST_READ, //What's the meaning?
IOobject::AUTO_WRITE //What's the meaning?
),
mesh //What is it?
);

[alexeym]

Hi,

Documentation is useful from time to time: http://cpp.openfoam.org/v4/a01196.html#details

And mesh is mesh object created within createMesh.H file, which is included before createFields.H.

[alimea]

Originally Posted by alexeym

Hi,

Documentation is useful from time to time: http://cpp.openfoam.org/v4/a01196.html#details

And mesh is mesh object created within createMesh.H file, which is included before createFields.H.

Dear Alexey
According to what I have found out, we call the mesh file by using this command. is it true? If yes, why do we need mesh at the middle of reading T from initial condition?

another question:
I want to change laplacianFoam to solve this equation:
laplacian(sai)=omega
is this procedure true:
1- defining sai and omega in createFilelds.H:

volScalarField sai
(
IOobject
(
"sai",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
mesh
);


volScalarField omega
(
IOobject
(
"omega",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
mesh
);

2- in file mylaplacian.C :

/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd | Copyright (C) 2011 OpenFOAM Foundation
\\/ M anipulation |
-------------------------------------------------------------------------------

#include "fvCFD.H"
#include "simpleControl.H"

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

int main(int argc, char *argv[])
{
#include "setRootCase.H"

#include "createTime.H"
#include "createMesh.H"
#include "createFields.H"

simpleControl simple(mesh);

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

Info<< "\nCalculating temperature distribution\n" << endl;

while (simple.loop())
{
Info<< "Time = " << runTime.timeName() << nl << endl;

while (simple.correctNonOrthogonal())
{
solve(fvm::laplacian(sai) == omega);

#include "write.H"

Info<< "ExecutionTime = " << runTime.elapsedCpuTime() << " s"
<< " ClockTime = " << runTime.elapsedClockTime() << " s"
<< nl << endl;
}

Info<< "End\n" << endl;

return 0;
}


3- debuging the code

[alexeym]

Hi,

Not quite sure I have got what you tried to say, in particular

Originally Posted by alimea

According to what I have found out, we call the mesh file by using this command. is it true? If yes, why do we need mesh at the middle of reading T from initial condition?

This one is completely beyond my mental capabilities. Every volume field needs reference to mesh, since inside the file only list of values is stored. That is why mesh is one of the parameters in volScalarField constructor.

another question:
I want to change laplacianFoam to solve this equation:
laplacian(sai)=omega
is this procedure true:
...

You have problem with brackets in your code. write.H header in laplacianFoam assumes that diffused scalar if called T, calculates gradient of T and then writes results. Since you would like to operate on the field called sai, you do not need write.H, just use runTime.write(). The rest is more or less correct for the problem you have described.

[olesen]

Originally Posted by alimea

Dear Alexey
According to what I have found out, we call the mesh file by using this command. is it true? If yes, why do we need mesh at the middle of reading T from initial condition?

volScalarField sai
( 
     IOobject
     ( 
        "sai", 
        runTime.timeName(), 
        mesh, 
        IOobject::MUST_READ,
        IOobject::AUTO_WRITE
     ), 
     mesh
);

The first 'mesh' (as part of the IOobject) provides the object-registry where the field will be read/written - the path of the case, the mesh region (normally defaultRegion, but could be multi-region).
The second 'mesh' is the reference where your field will be attached to.

/mark

[alimea]

Originally Posted by olesen

The first 'mesh' (as part of the IOobject) provides the object-registry where the field will be read/written - the path of the case, the mesh region (normally defaultRegion, but could be multi-region).
The second 'mesh' is the reference where your field will be attached to.

/mark

I think I have to learn more about objectRegistry.
Thanks