[hchen]

Hi,

I am pretty new to Openfoam and now trying to dig into the code.

If anybody can explain what is autoPtr, I met it several times but can not find any information about it. eg.

autoPtr<motionSolver> motionPtr_

Thanks!

Best regards
Hao

[jhoepken]

Hi Hao,

an autoPtr<T> is a smart pointer, which is basically "nothing more" than a wrapper around C++ pointers and handles e.g. garbage collection in an automatic fashion. Resources are released automatically, when they are out of scope.

Good luck with the dynamic meshes

Jens

[eric.m.tridas]

So if I understand correctly, using "autoPtr<T>" is preferable to using "new T()"?

[jhoepken]

autoPtr<T> myVar is preferable to T* myVar.

[eric.m.tridas]

That makes sense. Thanks!

[jhoepken]

No problemo

[hchen]

Hi Jens,

Thanks very much!

And one more question is that I can see in dynamic motion solver fv mesh, there are displacement laplacian and velocity laplacian, but I found one more mesh class called laplace...which equation does it solve? I can not find the source code of it...

Also waiting for your Openfoam book!

Hao

Originally Posted by jhoepken

Hi Hao,

an autoPtr<T> is a smart pointer, which is basically "nothing more" than a wrapper around C++ pointers and handles e.g. garbage collection in an automatic fashion. Resources are released automatically, when they are out of scope.

Good luck with the dynamic meshes

Jens

[jhoepken]

There are several types of motionSolvers:

1. componentDisplacement
2. componentVelocity
3. displacement
4. velocity

These are all virtual base classes for actual implementations motionSolvers. Look in $FOAM_SRC/fvMotionSolver/fvMotionSolvers (assuming you have the vanilla version of OpenFOAM).

For displacementLaplacianFvMotionSolver it solves Laplace equation:

void Foam::displacementLaplacianFvMotionSolver::solve()
{
    // The points have moved so before interpolation update
    // the motionSolver accordingly
    movePoints(fvMesh_.points());

    diffusivity().correct();
    pointDisplacement_.boundaryField().updateCoeffs();

    Foam::solve
    (
        fvm::laplacian
        (
            diffusivity().operator()(),
            cellDisplacement_,
            "laplacian(diffusivity,cellDisplacement)"
        )
    );
}

[hchen]

Hi Jens,

I see, thank you!

Another thing is when I select some diffusivity models, say exponential or quadratic, the error shows that: attempt to read beyond EOF, but normally uniform diffusivity is OK...Do you have any idea about the reason?

Best regards
Hao

Originally Posted by jhoepken

There are several types of motionSolvers:

1. componentDisplacement
2. componentVelocity
3. displacement
4. velocity

These are all virtual base classes for actual implementations motionSolvers. Look in $FOAM_SRC/fvMotionSolver/fvMotionSolvers (assuming you have the vanilla version of OpenFOAM).

For displacementLaplacianFvMotionSolver it solves Laplace equation:

void Foam::displacementLaplacianFvMotionSolver::solve()
{
    // The points have moved so before interpolation update
    // the motionSolver accordingly
    movePoints(fvMesh_.points());

    diffusivity().correct();
    pointDisplacement_.boundaryField().updateCoeffs();

    Foam::solve
    (
        fvm::laplacian
        (
            diffusivity().operator()(),
            cellDisplacement_,
            "laplacian(diffusivity,cellDisplacement)"
        )
    );
}

[jhoepken]

Maybe you are missing a parameter? Or a semicolon? Look in the source code of the particular model you use, and check which parameters it requires.