[Haier]

Dear Foamers,

I have been struggling with a problem (similar to wave tank/basin) related to dynamic mesh where I am trying to apply an oscillating boundary. The following are the basic settings:

• OF v2.3.0 on Suse 13.1
• solver: interDyMFoam

In constant/dynamicMeshDict

dynamicFvMesh       dynamicMotionSolverFvMesh;
motionSolverLibs    ("libfvMotionSolvers.so");
solver              displacementLaplacian;
displacementLaplacianCoeffs
{
    diffusivity  inverseDistance (movingBody);
}

In 0/pointDisplacement

boundaryField
{
...
    sidePlane
    {   
        type            slip;
    }
...
    movingBody
    {
        type            oscillatingDisplacement;
        amplitude    (0 0 1.0);
        omega        1.0;
        value           uniform (0 0 0);
    }
}

also, in system/fvSolution.solvers:

    cellDisplacement
    {   
        solver          GAMG;
        tolerance       1e-8;
        relTol          0;  
        smoother        GaussSeidel;
        cacheAgglomeration true;
        nCellsInCoarsestLevel 10; 
        agglomerator    faceAreaPair;
        mergeLevels     1;  
    }   
    cellDisplacementFinal
    {   
        $cellDisplacement;
        tolerance       1e-8;
        relTol          0;  
    }

Here is part of the error message I got:

[0] #0  Foam::error::printStack(Foam::Ostream&) at ??:?
[0] #1  Foam::sigFpe::sigHandler(int) at ??:?
[0] #2   in "/lib64/libc.so.6"
[0] #3  Foam::GAMGSolver::scale(Foam::Field<double>&, Foam::Field<double>&, Foam::lduMatrix const&, Foam::FieldField<Foam::Field, double> const&, Foam::UPtrList<Foam::lduInterfaceField const> const&, Foam::Field<double> const&, unsigned char) const at ??:? 
[0] #4  Foam::GAMGSolver::Vcycle(Foam::PtrList<Foam::lduMatrix::smoother> const&, Foam::Field<double>&, Foam::Field<double> const&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::Field<double>&, Foam::PtrList<Foam::Field<double> >&, Foam::PtrList<Foam::Field<double> >&, unsigned char) const at ??:? 
[0] #5  Foam::GAMGSolver::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
[0] #6  Foam::fvMatrix<double>::solveSegregated(Foam::dictionary const&) at ??:?
[0] #7  Foam::fvMatrix<double>::solve(Foam::dictionary const&) at ??:?
[0] #8  
[0]  at ??:?
[0] #9  __libc_start_main in "/lib64/libc.so.6"
[0] #10  
[0]  at /home/abuild/rpmbuild/BUILD/glibc-2.18/csu/../sysdeps/x86_64/start.S:125

The error message seems to indicate something went wrong while using GAMG solver. When I visualized the mesh movement, weird "ripple" near moving boundary were observed on the "sidePlane" which is supposed to be flat, see attachment. "Ripple" occurred around t=0.699 and the simulation crashed shortly after (around t=0.793).

Right now I am doubting if the "slip" type BC is the cause. Anyone has experience to share or bother to give any comments?

Thanks,
H.