|
[Sponsors] |
![]() |
![]() |
#1 |
New Member
Jean-Pierre
Join Date: May 2014
Posts: 9
Rep Power: 12 ![]() |
Hello everyone,
I've been using OpenFOAM for a while though I'm not an expert. I have one problem with refinementRegions generation. I need 5 refinement boxes inside my mesh but when I run snappyHexMesh I only get one of these boxes (the first one). I've checked several times the coordinates and I've searched on the net and in the forum but I cannot find the solution. I have already succed to add refinement boxes in other cases but iin this one I just can't. Here is my snappyHexMesh dict : Code:
FoamFile { version 2.0; format ascii; class dictionary; object snappyHexMeshDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // // Which of the steps to run castellatedMesh true; snap true; addLayers true; // 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 { train.stl { type triSurfaceMesh; name train; } ballastAndWall.stl { type triSurfaceMesh; name ballastAndWall; } refinementBoxA //first rafinement box { type searchableBox; min (-90 -50 0);//min (-80 -50 0); max (80 50 35);//max (90 50 35); } refinementBoxB //second one { type searchableBox; min (-80 -20 0); max (70 20 20); } refinementBoxC //near vehicle region { type searchableBox; min (-60 -10 0); max (60 10 10); } refinementBoxD //train { type searchableBox; min (-40 -2 0); max (40 2 6); } refinementBoxE //underbody { type searchableBox; min (-35 -1.7 1.3); max ( 35 1.7 2.7); } }; // 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 10; // 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 1; // 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 "train.eMesh"; level 5; }*/ ); // 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 { train { // Surface-wise min and max refinement level level (5 6); // Optional specification of patch type (default is wall). No // constraint types (cyclic, symmetry) etc. are allowed. } ballastAndWall { // Surface-wise min and max refinement level level (5 6); } } // 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 { refinementBoxA { mode inside; levels ((1 1)); //Le 1 n'a aucune influence pour une box //------1 } refinementBoxB { mode inside; levels ((1 3)); //Le 1 n'a aucune influence pour une box } refinementBoxC { mode inside; levels ((1 4)); //Le 1 n'a aucune influence pour une box } refinementBoxD { mode inside; levels ((1 5)); //Le 1 n'a aucune influence pour une box } refinementBoxE { mode inside; levels ((1 6)); //Le 1 n'a aucune influence pour une box } } // 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 (10 10 40); // 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 true; } // 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 2.0; //- Number of mesh displacement relaxation iterations. nSolveIter 30; //- 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 false; //- Use castellatedMeshControls::features (default = true) explicitFeatureSnap true; //- Detect points on multiple surfaces (only for explicitFeatureSnap) multiRegionFeatureSnap false; } // 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 { /*train { nSurfaceLayers 7; }*/ } // Expansion factor for layer mesh expansionRatio 1.2; // 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. // is the thickness of the layer furthest away from the wall. // See relativeSizes parameter. finalLayerThickness 1; //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 17x! (didn't do anything in 17x) nGrow 0; // Advanced settings // When not to extrude surface. 0 is flat surface, 90 is when two faces // are perpendicular featureAngle 60; // At non-patched sides allow mesh to slip if extrusion direction makes // angle larger than slipFeatureAngle. slipFeatureAngle 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 17x! 90 degrees corresponds to 130 in 17x. minMedianAxisAngle 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 90;//90 //- Max skewness allowed. Set to <0 to disable. maxBoundarySkewness -1;//-1 maxInternalSkewness -1;//-1 //- 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 180;//180 //- Minimum projected area v.s. actual area. Set to -1 to disable. minFlatness -1; //- 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-17; minTetQuality 1e-30; //- Minimum face area. Set to <0 to disable. minArea -1;//-1 //- Minimum face twist. Set to <-1 to disable. dot product of face normal //- and face centre triangles normal minTwist -2;//-2 //- minimum normalised cell determinant //- 1 = hex, <= 0 = folded or flattened illegal cell minDeterminant 0.001; //- minFaceWeight (0 -> 0.5) minFaceWeight 0.02;//0.02 //- 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; } // Advanced // Write flags writeFlags ( layerFields // write volScalarField for layer coverage ); // Merge tolerance. Is fraction of overall bounding box of initial mesh. // Note: the write tolerance needs to be higher than this. mergeTolerance 1e-6; Cheers |
|
![]() |
![]() |
![]() |
![]() |
#2 |
Retired Super Moderator
Bruno Santos
Join Date: Mar 2009
Location: Lisbon, Portugal
Posts: 10,981
Blog Entries: 45
Rep Power: 128 ![]() ![]() ![]() ![]() ![]() ![]() |
Greetings Jean-Pierre and welcome to the forum!
This one seemed easy to spot... Notice this line? Code:
maxLocalCells 100000; ![]() Best regards, Bruno
__________________
|
|
![]() |
![]() |
![]() |
![]() |
#3 |
New Member
Jean-Pierre
Join Date: May 2014
Posts: 9
Rep Power: 12 ![]() |
Oh dear... Thanks. I don't know how I didn't checked that before... I'm going to change it and reply back if it works.
Thank-you Bruno! Ciao |
|
![]() |
![]() |
![]() |
![]() |
#4 |
New Member
Jean-Pierre
Join Date: May 2014
Posts: 9
Rep Power: 12 ![]() |
Hi again!
A little update : It worked perfectly! Thank you! |
|
![]() |
![]() |
![]() |
Tags |
boxes, refinementregion, snappyhesmeshdict |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
refinementRegions is undefined | Gohu8 | OpenFOAM Running, Solving & CFD | 1 | August 30, 2017 04:20 |
[snappyHexMesh] snappy not using all refinementRegions and refinementSurfaces | suryansh | OpenFOAM Meshing & Mesh Conversion | 0 | June 6, 2016 07:20 |
[snappyHexMesh] refinementRegions in 3D | Harak | OpenFOAM Meshing & Mesh Conversion | 2 | July 30, 2015 12:54 |
[snappyHexMesh] refinementRegions does not accept two directives per geometry part | louisgag | OpenFOAM Meshing & Mesh Conversion | 0 | June 30, 2015 05:50 |
[Other] Rotation of refinementRegions in Snappy | Ruli | OpenFOAM Meshing & Mesh Conversion | 0 | December 13, 2013 19:16 |