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  • snappyHexMesh error

    Posted by Srinivas on February 27, 2023 at 6:22 am

    below is my SnappyHexMeshDict, with this setup Iam getting internal mesh. I dont Know why?

    i have set the locationinMesh outside the geometry but inside the domain.

     

    /*——————————–*- C++ -*———————————-*\
    | ========= | |
    | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
    | \\ / O peration | Version: v2212 |
    | \\ / A nd | Website: http://www.openfoam.com |
    | \\/ M anipulation | |
    \*—————————————————————————*/
    FoamFile
    {
    version 2.0;
    format ascii;
    class dictionary;
    object snappyHexMeshDict;
    }
    // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

    // Which of the steps to run
    castellatedMesh true;
    snap true;
    addLayers false;

    // Geometry. Definition of all surfaces. All surfaces are of class
    // searchableSurface.
    // Surfaces are used
    // – to specify refinement for any mesh cell intersecting it
    // – to specify refinement for any mesh cell inside/outside/near
    // – to ‘snap’ the mesh boundary to the surface
    geometry
    {
    innerCylinder.stl
    {
    type triSurfaceMesh;
    name innerCylinder;
    regions
    {
    CATIASTL
    {
    name innerCylinder;
    }
    }
    }
    innerCylinderSmall.stl
    {
    type triSurfaceMesh;
    name innerCylinderSmall;
    regions
    {
    CATIASTL
    {
    name innerCylinderSmall;
    }
    }
    }
    outerCylinder.stl
    {
    type triSurfaceMesh;
    name outerCylinder;
    regions
    {
    CATIASTL
    {
    name outerCylinder;
    }
    }
    }
    propellerTip.stl
    {
    type triSurfaceMesh;
    name propellerTip;
    regions
    {
    CATIASTL
    {
    name propellerTip;
    }
    }
    }

    }

    // Settings for the castellatedMesh generation.
    castellatedMeshControls
    {

    // Refinement parameters
    // ~~~~~~~~~~~~~~~~~~~~~

    // If local number of cells is >= maxLocalCells on any processor
    // switches from from refinement followed by balancing
    // (current method) to (weighted) balancing before refinement.
    maxLocalCells 100000;

    // Overall cell limit (approximately). Refinement will stop immediately
    // upon reaching this number so a refinement level might not complete.
    // Note that this is the number of cells before removing the part which
    // is not ‘visible’ from the keepPoint. The final number of cells might
    // actually be a lot less.
    maxGlobalCells 2000000;

    // The surface refinement loop might spend lots of iterations refining just a
    // few cells. This setting will cause refinement to stop if <= minimumRefine
    // are selected for refinement. Note: it will at least do one iteration
    // (unless the number of cells to refine is 0)
    minRefinementCells 0;

    // Allow a certain level of imbalance during refining
    // (since balancing is quite expensive)
    // Expressed as fraction of perfect balance (= overall number of cells /
    // nProcs). 0=balance always.
    maxLoadUnbalance 0.10;

    // Number of buffer layers between different levels.
    // 1 means normal 2:1 refinement restriction, larger means slower
    // refinement.
    nCellsBetweenLevels 2;

     

    // Explicit feature edge refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    // Specifies a level for any cell intersected by its edges.
    // This is a featureEdgeMesh, read from constant/triSurface for now.
    features
    (
    {
    file “innerCylinderSmall.eMesh”;
    level 4;
    }
    {
    file “outerCylinder.eMesh”;
    level 0;
    }
    {
    file “propellerTip.eMesh”;
    level 4;
    }
    // {
    // file “propellerStem1.eMesh”;
    // level 4;
    // }

    );

     

    // Surface based refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~

    // Specifies two levels for every surface. The first is the minimum level,
    // every cell intersecting a surface gets refined up to the minimum level.
    // The second level is the maximum level. Cells that ‘see’ multiple
    // intersections where the intersections make an
    // angle > resolveFeatureAngle get refined up to the maximum level.

    refinementSurfaces
    {
    innerCylinderSmall
    {
    level (4 4);

    faceType boundary;
    cellZone innerCylinderSmall;
    faceZone innerCylinderSmall;
    cellZoneInside inside;
    }
    outerCylinder
    {
    level (0 0);
    }
    propellerTip
    {
    level (4 5);
    }

    }

    // Resolve sharp angles
    resolveFeatureAngle 30;

    // Region-wise refinement
    // ~~~~~~~~~~~~~~~~~~~~~~

    // Specifies refinement level for cells in relation to a surface. One of
    // three modes
    // – distance. ‘levels’ specifies per distance to the surface the
    // wanted refinement level. The distances need to be specified in
    // descending order.
    // – inside. ‘levels’ is only one entry and only the level is used. All
    // cells inside the surface get refined up to the level. The surface
    // needs to be closed for this to be possible.
    // – outside. Same but cells outside.

    refinementRegions
    {
    innerCylinder
    {
    mode inside;
    levels ((1E15 3));
    }
    innerCylinderSmall
    {
    mode inside;
    levels ((1E15 4));
    }
    }

    // Mesh selection
    // ~~~~~~~~~~~~~~

    // After refinement patches get added for all refinementSurfaces and
    // all cells intersecting the surfaces get put into these patches. The
    // section reachable from the locationInMesh is kept.
    // NOTE: This point should never be on a face, always inside a cell, even
    // after refinement.
    locationInMesh (0.01 -0.5 900);

    // Whether any faceZones (as specified in the refinementSurfaces)
    // are only on the boundary of corresponding cellZones or also allow
    // free-standing zone faces. Not used if there are no faceZones.
    allowFreeStandingZoneFaces false;
    }

     

    // Settings for the snapping.
    snapControls
    {
    //- Number of patch smoothing iterations before finding correspondence
    // to surface
    nSmoothPatch 3;

    //- Relative distance for points to be attracted by surface feature point
    // or edge. True distance is this factor times local
    // maximum edge length.
    tolerance 4.0; // 1.0;

    //- Number of mesh displacement relaxation iterations.
    nSolveIter 300;

    //- Maximum number of snapping relaxation iterations. Should stop
    // before upon reaching a correct mesh.
    nRelaxIter 5;

    // Feature snapping

    // Number of feature edge snapping iterations.
    // Leave out altogether to disable.
    nFeatureSnapIter 10;

    // Detect (geometric only) features by sampling the surface
    // (default=false).
    implicitFeatureSnap true;

    // Use castellatedMeshControls::features (default = true)
    explicitFeatureSnap false;

    // Detect features between multiple surfaces
    // (only for explicitFeatureSnap, default = false)
    multiRegionFeatureSnap true;
    }

     

    // Settings for the layer addition.
    addLayersControls
    {
    // Are the thickness parameters below relative to the undistorted
    // size of the refined cell outside layer (true) or absolute sizes (false).
    relativeSizes true;

    // Per final patch (so not geometry!) the layer information
    layers
    {
    }

    // Expansion factor for layer mesh
    expansionRatio 1.0;

    // Wanted thickness of final added cell layer. If multiple layers
    // is the thickness of the layer furthest away from the wall.
    // Relative to undistorted size of cell outside layer.
    // See relativeSizes parameter.
    finalLayerThickness 0.3;

    // Minimum thickness of cell layer. If for any reason layer
    // cannot be above minThickness do not add layer.
    // Relative to undistorted size of cell outside layer.
    minThickness 0.1;

    // If points get not extruded do nGrow layers of connected faces that are
    // also not grown. This helps convergence of the layer addition process
    // close to features.
    // Note: changed(corrected) w.r.t 1.7.x! (didn’t do anything in 1.7.x)
    nGrow 0;

    // Advanced settings

    // When not to extrude surface. 0 is flat surface, 90 is when two faces
    // are perpendicular
    featureAngle 30;

    // Maximum number of snapping relaxation iterations. Should stop
    // before upon reaching a correct mesh.
    nRelaxIter 3;

    // Number of smoothing iterations of surface normals
    nSmoothSurfaceNormals 1;

    // Number of smoothing iterations of interior mesh movement direction
    nSmoothNormals 3;

    // Smooth layer thickness over surface patches
    nSmoothThickness 10;

    // Stop layer growth on highly warped cells
    maxFaceThicknessRatio 0.5;

    // Reduce layer growth where ratio thickness to medial
    // distance is large
    maxThicknessToMedialRatio 0.3;

    // Angle used to pick up medial axis points
    // Note: changed(corrected) w.r.t 1.7.x! 90 degrees corresponds to 130
    // in 1.7.x.
    minMedialAxisAngle 90;

    // Create buffer region for new layer terminations
    nBufferCellsNoExtrude 0;

    // Overall max number of layer addition iterations. The mesher will exit
    // if it reaches this number of iterations; possibly with an illegal
    // mesh.
    nLayerIter 50;
    }

     

    // Generic mesh quality settings. At any undoable phase these determine
    // where to undo.
    meshQualityControls
    {
    //- Maximum non-orthogonality allowed. Set to 180 to disable.
    maxNonOrtho 65;

    //- Max skewness allowed. Set to <0 to disable.
    maxBoundarySkewness 20;
    maxInternalSkewness 4;

    //- Max concaveness allowed. Is angle (in degrees) below which concavity
    // is allowed. 0 is straight face, <0 would be convex face.
    // Set to 180 to disable.
    maxConcave 80;

    //- Minimum pyramid volume. Is absolute volume of cell pyramid.
    // Set to a sensible fraction of the smallest cell volume expected.
    // Set to very negative number (e.g. -1E30) to disable.
    minVol 1e-13;

    //- Minimum quality of the tet formed by the face-centre
    // and variable base point minimum decomposition triangles and
    // the cell centre. This has to be a positive number for tracking
    // to work. Set to very negative number (e.g. -1E30) to
    // disable.
    // <0 = inside out tet,
    // 0 = flat tet
    // 1 = regular tet
    minTetQuality -1; // 1e-30;

    //- Minimum face area. Set to <0 to disable.
    minArea -1;

    //- Minimum face twist. Set to <-1 to disable. dot product of face normal
    // and face centre triangles normal
    minTwist 0.01;

    //- Minimum normalised cell determinant
    // 1 = hex, <= 0 = folded or flattened illegal cell
    minDeterminant 0.001;

    //- minFaceWeight (0 -> 0.5)
    minFaceWeight 0.05;

    //- minVolRatio (0 -> 1)
    minVolRatio 0.01;

    //must be >0 for Fluent compatibility
    minTriangleTwist -1;

    // Advanced

    //- Number of error distribution iterations
    nSmoothScale 4;
    //- Amount to scale back displacement at error points
    errorReduction 0.75;

    // Optional : some meshing phases allow usage of relaxed rules.
    // See e.g. addLayersControls::nRelaxedIter.
    relaxed
    {
    //- Maximum non-orthogonality allowed. Set to 180 to disable.
    maxNonOrtho 75;
    }
    }

     

    // Merge tolerance. Is fraction of overall bounding box of initial mesh.
    // Note: the write tolerance needs to be higher than this.
    mergeTolerance 1e-6;

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

    Barış Bicer replied 1 year, 1 month ago 2 Members · 17 Replies
  • 17 Replies
  • Srinivas

    Member
    February 27, 2023 at 6:23 am

  • Srinivas

    Member
    February 27, 2023 at 6:47 am

    ignore Above Dict, its wrong Dict. below is correct SnappyHexMeshDict.

     

    /*——————————–*- C++ -*———————————-*\
    | ========= | |
    | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
    | \\ / O peration | Version: 2.2.0 |
    | \\ / A nd | Web: http://www.OpenFOAM.org |
    | \\/ M anipulation | |
    \*—————————————————————————*/
    FoamFile
    {
    version 2.0;
    format ascii;
    class dictionary;
    object snappyHexMeshDict;
    }
    // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

    // Which of the steps to run
    castellatedMesh true; // make basic mesh ?
    snap true; // decide to snap back to surface ?
    addLayers false; // decide to add viscous layers ?

    geometry // Load in STL files here
    {
    STOLFuselage.stl {type triSurfaceMesh; name STOLFuselage;}
    STOLgear.stl {type triSurfaceMesh; name STOLgear;}
    STOLleftcanard.stl {type triSurfaceMesh; name STOLleftcanard;}
    STOLleftrudder.stl {type triSurfaceMesh; name STOLleftrudder;}
    STOLleftwing.stl {type triSurfaceMesh; name STOLleftwing;}
    STOLmotorcase.stl {type triSurfaceMesh; name STOLmotorcase;}
    STOLrightcanard.stl {type triSurfaceMesh; name STOLrightcanard;}
    STOLrightrudder.stl {type triSurfaceMesh; name STOLrightrudder;}
    STOLrightwing.stl {type triSurfaceMesh; name STOLrightwing;}

    refinementBox
    {
    type searchableBox;
    min (-6000 -600 -600);
    max ( 2000 600 600);
    }

    };

    castellatedMeshControls
    {
    maxLocalCells 10000000; //max cells per CPU core
    maxGlobalCells 20000000; //max cells to use before mesh deletion step
    minRefinementCells 10; //was 0 – zero means no bad cells are allowed during refinement stages
    maxLoadUnbalance 0.10;
    nCellsBetweenLevels 4; // expansion factor between each high & low refinement zone

    // Explicit feature edge refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    features // taken from STL from each .eMesh file created by “SurfaceFeatureExtract” command
    (
    {file “STOLrightcanard.eMesh”; level 3;}
    {file “STOLFuselage.eMesh”; level 3;}
    {file “STOLgear.eMesh”; level 4;}
    {file “STOLleftcanard.eMesh”; level 3;}
    {file “STOLleftrudder.eMesh”; level 3;}
    {file “STOLleftwing.eMesh”; level 3;}
    {file “STOLmotorcase.eMesh”; level 4;}
    {file “STOLrightrudder.eMesh”; level 3;}
    {file “STOLrightwing.eMesh”; level 3;}

    );

    // Surface based refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~

    refinementSurfaces // Surface-wise min and max refinement level
    {
    STOLrightcanard {level (3 3);}
    STOLFuselage {level (3 3);}
    STOLgear {level (4 4);}
    STOLleftcanard {level (3 3);}
    STOLleftrudder {level (3 3);}
    STOLleftwing {level (3 3);} // was 4 4
    STOLmotorcase {level (4 4);} // was 4 4
    STOLrightrudder {level (3 3);}
    STOLrightwing {level (3 3);} // was 4 4

    }

    resolveFeatureAngle 5; // Resolve sharp angles // Default 30
    refinementRegions // In descending levels of fine-ness
    {

    refinementBox
    {
    mode inside;
    levels ((1E15 4));
    }

    }

    locationInMesh (-3000 600 600); //to decide which side of mesh to keep **
    allowFreeStandingZoneFaces true;
    }

    // Settings for the snapping.
    snapControls
    {
    nSmoothPatch 3;
    tolerance 4.0;
    nSolveIter 30;
    nRelaxIter 5;
    nFeatureSnapIter 15; // default is 10

    // New settings from openfoam 2.2 onwards for SHMesh

    implicitFeatureSnap false; // default is false – detects without doing surfaceFeatureExtract
    explicitFeatureSnap true; // default is true
    multiRegionFeatureSnap false; // deafault is false – detects features between multiple surfaces

    }

     

    // Settings for the layer addition.
    addLayersControls //add the PATCH names from inSTOLleftwing the STL file so STLpatchName_inSTOLleftwingSTLName
    {
    relativeSizes true; // was true
    layers
    {
    STOLrightcanard
    {nSurfaceLayers 8;} // was 3

    STOLFuselage
    {nSurfaceLayers 8;} // was 3

    STOLgear
    {nSurfaceLayers 8;} // was 3

    STOLleftcanard
    {nSurfaceLayers 8;} // was 3

    STOLleftrudder
    {nSurfaceLayers 8;} // was 3

    STOLleftwing
    {nSurfaceLayers 8;} // was 3

    STOLmotorcase
    {nSurfaceLayers 8;} // was 3

    STOLrightrudder
    {nSurfaceLayers 8;} // was 3

     

    STOLrightwing
    {nSurfaceLayers 8;} // was 3

    }

    expansionRatio 1.05;
    finalLayerThickness 0.1; //was 0.00016
    minThickness 0.001; //was 0.00008
    nGrow -1; // was 1

    // Advanced settings

    featureAngle 170; // was 70 //- When not to extrude surface. 0 is flat, 90 is right angle.
    nRelaxIter 3; //- Max# of snapping relaxation iter. Should sSTOLleftcanard before upon reaching a correct mesh.
    nSmoothSurfaceNormals 1; // Number of smoothing iterations of surface normals
    nSmoothNormals 3; // Number of smoothing iterations of interior mesh movement direction
    nSmoothThickness 10; // Smooth layer thickness over surface patches
    maxFaceThicknessRatio 0.5; // SSTOLleftcanard layer growth on highly warped cells
    maxThicknessToMedialRatio 0.3; // Reduce layer growth where ratio thickness to medial distance is large
    minMedianAxisAngle 130; // Angle used to pick up medial axis points
    nBufferCellsNoExtrude 0; // Create buffer region for new layer terminations
    nLayerIter 25; // Overall max number of layer addition iterations
    }

     

    // Generic mesh quality settings. At any undoable phase these determine
    // where to undo.
    meshQualityControls
    {
    maxNonOrtho 65;
    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;

    // Advanced

    nSmoothScale 4;
    errorReduction 0.75;
    }

    // Advanced

    debug 0;

    // Merge tolerance. Is fraction of overall bounding box of initial mesh.
    // Note: the write tolerance needs to be higher than this.
    mergeTolerance 1E-6;

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

  • Srinivas

    Member
    February 27, 2023 at 7:20 am

    when I reduce the surface level then its not creating the internal Mesh.

    below surface you can see with compare to above.

    nCellsBetweenLevels 4; // expansion factor between each high & low refinement zone

    // Explicit feature edge refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    features // taken from STL from each .eMesh file created by “SurfaceFeatureExtract” command
    (
    {file “STOLrightcanard.eMesh”; level 3;}
    {file “STOLFuselage.eMesh”; level 3;}
    {file “STOLgear.eMesh”; level 4;}
    {file “STOLleftcanard.eMesh”; level 3;}
    {file “STOLleftrudder.eMesh”; level 3;}
    {file “STOLleftwing.eMesh”; level 3;}
    {file “STOLmotorcase.eMesh”; level 4;}
    {file “STOLrightrudder.eMesh”; level 3;}
    {file “STOLrightwing.eMesh”; level 3;}

    );

    // Surface based refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~

    refinementSurfaces // Surface-wise min and max refinement level
    {
    STOLrightcanard {level (3 3);}
    STOLFuselage {level (3 3);}
    STOLgear {level (4 4);}
    STOLleftcanard {level (3 3);}
    STOLleftrudder {level (3 3);}
    STOLleftwing {level (3 3);} // was 4 4
    STOLmotorcase {level (4 4);} // was 4 4
    STOLrightrudder {level (3 3);}
    STOLrightwing {level (3 3);} // was 4 4

    }

    resolveFeatureAngle 5; // Resolve sharp angles // Default 30
    refinementRegions // In descending levels of fine-ness
    {

    refinementBox
    {
    mode inside;
    levels ((1E15 4));
    }

    }

  • Srinivas

    Member
    February 27, 2023 at 7:21 am

  • Srinivas

    Member
    February 27, 2023 at 7:31 am

    I am verry sorry again and again Iam giving you a wrong Dict. i ahave posted the same Dict aging.

    my main problem is if i set the surface level more then it create the internal mesh. when I reduce the surafece level then it is not creating the internal mesh. this time I am giving you the correct SnappyHex mesh which create the internal mesh. when I set the refinment level 3 it is not creating the internal mesh. but when I increase the refinment level 6 it create the internal mesh. now I am giving you the snappyHexMeshDiuct which create internal Mesh

    /*——————————–*- C++ -*———————————-*\
    | ========= | |
    | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
    | \\ / O peration | Version: 2.2.0 |
    | \\ / A nd | Web: http://www.OpenFOAM.org |
    | \\/ M anipulation | |
    \*—————————————————————————*/
    FoamFile
    {
    version 2.0;
    format ascii;
    class dictionary;
    object snappyHexMeshDict;
    }
    // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

    // Which of the steps to run
    castellatedMesh true; // make basic mesh ?
    snap true; // decide to snap back to surface ?
    addLayers false; // decide to add viscous layers ?

    geometry // Load in STL files here
    {
    STOLFuselage.stl {type triSurfaceMesh; name STOLFuselage;}
    STOLgear.stl {type triSurfaceMesh; name STOLgear;}
    STOLleftcanard.stl {type triSurfaceMesh; name STOLleftcanard;}
    STOLleftrudder.stl {type triSurfaceMesh; name STOLleftrudder;}
    STOLleftwing.stl {type triSurfaceMesh; name STOLleftwing;}
    STOLmotorcase.stl {type triSurfaceMesh; name STOLmotorcase;}
    STOLrightcanard.stl {type triSurfaceMesh; name STOLrightcanard;}
    STOLrightrudder.stl {type triSurfaceMesh; name STOLrightrudder;}
    STOLrightwing.stl {type triSurfaceMesh; name STOLrightwing;}

    refinementBox
    {
    type searchableBox;
    min (-6000 -600 -600);
    max ( 2000 600 600);
    }

    };

    castellatedMeshControls
    {
    maxLocalCells 10000000; //max cells per CPU core
    maxGlobalCells 20000000; //max cells to use before mesh deletion step
    minRefinementCells 10; //was 0 – zero means no bad cells are allowed during refinement stages
    maxLoadUnbalance 0.10;
    nCellsBetweenLevels 4; // expansion factor between each high & low refinement zone

    // Explicit feature edge refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    features // taken from STL from each .eMesh file created by “SurfaceFeatureExtract” command
    (
    {file “STOLrightcanard.eMesh”; level 6;}
    {file “STOLFuselage.eMesh”; level 5;}
    {file “STOLgear.eMesh”; level 7;}
    {file “STOLleftcanard.eMesh”; level 6;}
    {file “STOLleftrudder.eMesh”; level 6;}
    {file “STOLleftwing.eMesh”; level 6;}
    {file “STOLmotorcase.eMesh”; level 7;}
    {file “STOLrightrudder.eMesh”; level 6;}
    {file “STOLrightwing.eMesh”; level 6;}

    );

    // Surface based refinement
    // ~~~~~~~~~~~~~~~~~~~~~~~~

    refinementSurfaces // Surface-wise min and max refinement level
    {
    STOLrightcanard {level (6 6);}
    STOLFuselage {level (5 5);}
    STOLgear {level (7 7);}
    STOLleftcanard {level (6 6);}
    STOLleftrudder {level (6 6);}
    STOLleftwing {level (6 6);} // was 4 4
    STOLmotorcase {level (7 7);} // was 4 4
    STOLrightrudder {level (6 6);}
    STOLrightwing {level (6 6);} // was 4 4

    }

    resolveFeatureAngle 5; // Resolve sharp angles // Default 30
    refinementRegions // In descending levels of fine-ness
    {

    refinementBox
    {
    mode inside;
    levels ((1E15 4));
    }

    }

    locationInMesh (-3000 100.212 100.2512); //to decide which side of mesh to keep **
    allowFreeStandingZoneFaces true;
    }

    // Settings for the snapping.
    snapControls
    {
    nSmoothPatch 3;
    tolerance 4.0;
    nSolveIter 30;
    nRelaxIter 5;
    nFeatureSnapIter 15; // default is 10

    // New settings from openfoam 2.2 onwards for SHMesh

    implicitFeatureSnap false; // default is false – detects without doing surfaceFeatureExtract
    explicitFeatureSnap true; // default is true
    multiRegionFeatureSnap false; // deafault is false – detects features between multiple surfaces

    }

     

    // Settings for the layer addition.
    addLayersControls //add the PATCH names from inSTOLleftwing the STL file so STLpatchName_inSTOLleftwingSTLName
    {
    relativeSizes true; // was true
    layers
    {
    STOLrightcanard
    {nSurfaceLayers 8;} // was 3

    }

    expansionRatio 1.05;
    finalLayerThickness 0.1; //was 0.00016
    minThickness 0.001; //was 0.00008
    nGrow -1; // was 1

    // Advanced settings

    featureAngle 170; // was 70 //- When not to extrude surface. 0 is flat, 90 is right angle.
    nRelaxIter 3; //- Max# of snapping relaxation iter. Should sSTOLleftcanard before upon reaching a correct mesh.
    nSmoothSurfaceNormals 1; // Number of smoothing iterations of surface normals
    nSmoothNormals 3; // Number of smoothing iterations of interior mesh movement direction
    nSmoothThickness 10; // Smooth layer thickness over surface patches
    maxFaceThicknessRatio 0.5; // SSTOLleftcanard layer growth on highly warped cells
    maxThicknessToMedialRatio 0.3; // Reduce layer growth where ratio thickness to medial distance is large
    minMedianAxisAngle 130; // Angle used to pick up medial axis points
    nBufferCellsNoExtrude 0; // Create buffer region for new layer terminations
    nLayerIter 25; // Overall max number of layer addition iterations
    }

     

    // Generic mesh quality settings. At any undoable phase these determine
    // where to undo.
    meshQualityControls
    {
    maxNonOrtho 65;
    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;

    // Advanced

    nSmoothScale 4;
    errorReduction 0.75;
    }

    // Advanced

    debug 0;

    // Merge tolerance. Is fraction of overall bounding box of initial mesh.
    // Note: the write tolerance needs to be higher than this.
    mergeTolerance 1E-6;

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

     

  • Barış Bicer

    Moderator
    February 28, 2023 at 9:46 am

    First please when you are sure about the question with correct data then post here.

    I read your all messages and what I see that your geometry region dimension is around 3000 something. Dont forget that OpenFOAM always using meter as dimension. So it means that your domain is around 3km????? I think that from CATIA you export geometries as mm and not converted to meter before using in OpenFOAM. First correct it and then try with same refinement. Meshing inside is related to surface quality…

  • Srinivas

    Member
    March 3, 2023 at 4:42 am

    thank you sir!

    I export the geometry in m from CATIA, previously it was in mm.

    now its not creating internal mesh

     

  • Srinivas

    Member
    March 3, 2023 at 4:53 am

  • Srinivas

    Member
    March 3, 2023 at 4:54 am

    But it shows above error

     

  • Srinivas

    Member
    March 3, 2023 at 5:27 am

    i Have search this problem on open cfd online platform.

    It says its due to your username in ubuntu. using number in username gives this problem.

    Its true or not?

     

  • Barış Bicer

    Moderator
    March 4, 2023 at 7:11 pm

    No no it is not related to username. look at your force and moment values they are diverging. Most probably your initial conditions look wrong since you should check them your goes to diverge

  • Srinivas

    Member
    March 7, 2023 at 6:27 am

    I make changes in initial condition it run perfectly.

    but I am doing one validation case of UAV the pressure distribution is not correct. I will show you below.

    pressure on above the wing should be lees than the precure on the below the wing.

    I have done one validation case it was correct according to the reference paper which I have used.

  • Srinivas

    Member
    March 7, 2023 at 6:45 am

  • Srinivas

    Member
    March 7, 2023 at 6:47 am

  • Srinivas

    Member
    March 7, 2023 at 6:50 am

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