CFD Online Discussion Forums - [snappyHexMesh] SnappyHexMesh crashes on shell refinement

Dear all,

I am solving a heat transfer multi-region problem on a flow around a thin plate in a pipe.

For snappyHexMesh, blockMesh 40*80*40 works fine, but when I try to use a finer blockMesh 80*200*80, snappyHexMesh crashes with the following message (here are the last lines of the output):

Code:

Surface refinement iteration 4

------------------------------



Marked for refinement due to surface intersection          : 0 cells.

Marked for refinement due to curvature/regions             : 0 cells.

Determined cells to refine in = 6.71 s

Selected for refinement : 0 cells (out of 6699946)

Stopping refining since too few cells selected.





Removing mesh beyond surface intersections

------------------------------------------



Setting cellZones according to locationsInMesh:

Location : (0.0081 0.0001 0.0049)

    cellZone : fluid

Location : (0.0139 0.0001 0.0001)

    cellZone : pipe

Location : (0.0001 0.0001 0.0001)

    cellZone : plane



For cellZone fluid found point (0.0081 0.0001 0.0049) in global region 2 out of 5 regions.

For cellZone pipe found point (0.0139 0.0001 0.0001) in global region 1 out of 5 regions.

For cellZone plane found point (0.0001 0.0001 0.0001) in global region 3 out of 5 regions.

--> FOAM Warning : 

    From void Foam::meshRefinement::nearestFace(const labelUList&, const Foam::bitSet&, Foam::autoPtr<Foam::mapDistribute>&, Foam::labelList&, Foam::label) const

    in file meshRefinement/meshRefinement.C at line 515

    Did not visit some faces, e.g. face 0 at (-0.0195 -0.04975 -0.01975)

Keeping all cells containing inside points

Selected for keeping : 5331639 cells.

Edge intersection testing:

    Number of edges             : 17492259

    Number of edges to retest   : 739197

    Number of intersected edges : 1574622



Shell refinement iteration 0

----------------------------



Marked for refinement due to distance to explicit features : 0 cells.

Marked for refinement due to refinement shells             : 0 cells.

Determined cells to refine in = 32.12 s

Selected for internal refinement : 476207 cells (out of 5331639)

Edge intersection testing:

    Number of edges             : 27470895

    Number of edges to retest   : 20488144

Killed

Here is my snappyHexMesh file:

Code:

/*--------------------------------*- C++ -*----------------------------------*\

| =========                 |                                                 |

| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |

|  \\    /   O peration     | Version:  v2306                                 |

|   \\  /    A nd           | Website:  www.openfoam.com                      |

|    \\/     M anipulation  |                                                 |

\*---------------------------------------------------------------------------*/

FoamFile

{

    version     2.0;

    format      ascii;

    class       dictionary;

    object      snappyHexMeshDict;

}

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



castellatedMesh true;

snap            true;

addLayers       false;



geometry

{

    pipe.stl   { type triSurfaceMesh; name pipe; }

    inlet.stl  { type triSurfaceMesh; name inlet;  }

    outlet.stl { type triSurfaceMesh; name outlet; }

    plane.stl  { type triSurfaceMesh; name plane;

        regions

        {

            planeBackFace {name planeBackFace;}

            planeBottomFace {name planeBottomFace;}

            planeFrontFace {name planeFrontFace;}

            planeHole1 {name planeHole1;}

            planeHole2 {name planeHole2;}

            planeHole3 {name planeHole3;}

            planeHole4 {name planeHole4;}

            planeHole5 {name planeHole5;}

            planeHole6 {name planeHole6;}

            planetLeftFace {name planeLeftFace;}

            planeRightFace {name planeRightFace;}

            planeTopFace {name planeTopFace;}

        }

    }

}



castellatedMeshControls

{

    maxGlobalCells 15000000;

    maxLocalCells 5000000;

    minRefinementCells 0;

    nCellsBetweenLevels 3;



    features

    (

        { file "pipe.extendedFeatureEdgeMesh";   level 2; }

        { file "plane.extendedFeatureEdgeMesh";  level 2; }

    );



    refinementSurfaces

    {

        pipe   { level (2 2); }

        inlet  { level (2 2); patchInfo { type patch; } }

        outlet { level (2 2); patchInfo { type patch; } }

        plane  { level (2 2); patchInfo { type wall; }

            regions

            {

                planeHole1 { level (4 5); }

                planeHole2 { level (4 5); }

                planeHole3 { level (4 5); }

                planeHole4 { level (4 5); }

                planeHole5 { level (4 5); }

                planeHole6 { level (4 5); }

            }

        }

    }



    resolveFeatureAngle 30;



    refinementRegions { }



    locationsInMesh

    (

        ((0.0081 0.0001 0.0049) fluid )

        ((0.0139 0.0001 0.0001) pipe  )

        ((0.0001 0.0001 0.0001) plane )

    );

    allowFreeStandingZoneFaces false;

}



snapControls

{

    nSmoothPatch 3;

    tolerance 1.0;

    nSolveIter 100;

    nRelaxIter 5;

    nFeatureSnapIter 10;

    implicitFeatureSnap false;

    explicitFeatureSnap true;

    multiRegionFeatureSnap false;

}



addLayersControls

{

    relativeSizes false;



    layers 

    {

        reactorInnerWall { nSurfaceLayers 8; }

    }



    expansionRatio 1.2;

    finalLayerThickness 0.001;

    minThickness 0.0005;

    nGrow 0;

    featureAngle 80;

    nRelaxIter 5;

    nSmoothSurfaceNormals 1;

    nSmoothNormals 3;

    nSmoothThickness 10;

    maxFaceThicknessRatio 0.5;

    maxThicknessToMedialRatio 0.3;

    minMedialAxisAngle 90;

    nBufferCellsNoExtrude 0;

    nLayerIter 50;

    nRelaxedIter 20;

}



meshQualityControls

{

    maxNonOrtho 180;

    maxBoundarySkewness 20;

    maxInternalSkewness 4;

    maxConcave 80;

    minFlatness 0.5;

    minVol 1e-13;



    minTetQuality 1e-30;

    minArea -1;



    minTwist 0.02;

    minDeterminant 0.001;

    minFaceWeight 0.02;

    minVolRatio 0.01;

    minTriangleTwist -1;



    nSmoothScale 4;

    errorReduction 0.75;

}



mergeTolerance 1e-6;



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

I would very appreciate if someone could give me a hint on what is the reason for a crash? There is no clear error message in the output.

Thanks!

P.S. I was not sure about opening another trade, I am still solving the same task as in Multi-region mesh: improve mesh on interface fluid-solid, but my current question is different from the question stated there.