/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: v2012 | | \\ / A nd | Website: www.openfoam.com | | \\/ M anipulation | | \*---------------------------------------------------------------------------*/ FoamFile { version 2.0; format ascii; class dictionary; object snappyHexMeshDict; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // // Which of the steps to run castellatedMesh false; snap false; addLayers true; // Geometry. Definition of all surfaces. All surfaces are of class // searchableSurface. geometry {} // 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 1; // Explicit feature edge refinement // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // Specifies a level for any cell intersected by explicitly provided // edges. // This is a featureEdgeMesh, read from constant/triSurface for now. // Specify 'levels' in the same way as the 'distance' mode in the // refinementRegions (see below). The old specification // level 2; // is equivalent to // levels ((0 2)); features (); // 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 {} // Feature angle: // - used if min and max refinement level of a surface differ // - used if feature snapping (see snapControls below) is used 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 // increasing 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 {} // 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 location(s)InMesh is kept. // NOTE: This point should never be on a face, always inside a cell, even // after refinement. // // There are two different ways of specifying the regions to keep: // 1. a single locationInMesh. All the 'zoned' surfaces are marked as such // in the refinementSurfaces with the faceZone and cellZone keywords. // // or // // 2. multiple locationsInMesh, with per location the name of the cellZone. // This uses walking to determine zones and automatically creates // faceZones on the outside of cellZones. // Ad 1. Specify a single location and how to treat faces inbetween // cellZones locationInMesh (5 0.28 0.43); // 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; // Maximum relative distance for points to be attracted by surface. // True distance is this factor times local maximum edge length. // Note: changed(corrected) w.r.t 1.7.x! (1.7.x used 2* tolerance) 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; } // 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 false; // Expansion factor for layer mesh expansionRatio 1.0; firstLayerThickness 0.2e-3; // Minimum overall thickness of total layers. If for any reason layer // cannot be above minThickness do not add layer. // If relativeSizes this is relative to undistorted size of cell // outside layer.. minThickness 0.1e-3; // Per final patch (so not geometry!) the layer information layers { maxY { nSurfaceLayers 2; } minY { nSurfaceLayers 2; } A { nSurfaceLayers 2; } A_slave { nSurfaceLayers 2; } } // 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 // Static analysis of starting mesh // When not to extrude surface. 0 is flat surface, 90 is when two faces // are perpendicular featureAngle 130; // When to merge patch faces. Default is featureAngle //mergePatchFacesAngle 45; // Do not extrude around sharp edge if not both faces are extruded. // Default is 0.5*featureAngle. Set to -180 always attempt extrusion layerTerminationAngle -180; // Stop layer growth on highly warped cells maxFaceThicknessRatio 0.5; // Patch displacement // Number of smoothing iterations of surface normals nSmoothSurfaceNormals 1; // Smooth layer thickness over surface patches nSmoothThickness 10; // Medial axis analysis // 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; // Reduce layer growth where ratio thickness to medial // distance is large maxThicknessToMedialRatio 0.3; // Number of smoothing iterations of interior mesh movement direction nSmoothNormals 3; // Mesh shrinking // Optional: at non-patched sides allow mesh to slip if extrusion // direction makes angle larger than slipFeatureAngle. Default is // 0.5*featureAngle. slipFeatureAngle 30; // Maximum number of snapping relaxation iterations. Should stop // before upon reaching a correct mesh. nRelaxIter 5; // 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; // // // Max number of iterations after which relaxed meshQuality controls // // get used. Up to nRelaxedIter it uses the settings in // // meshQualityControls, // // after nRelaxedIter it uses the values in // // meshQualityControls::relaxed. // nRelaxedIter 20; // // // Additional reporting: if there are just a few faces where there // // are mesh errors (after adding the layers) print their face centres. // // This helps in tracking down problematic mesh areas. // //additionalReporting true; } // Generic mesh quality settings. At any undoable phase these determine // where to undo. meshQualityControls { // Specify mesh quality constraints in separate dictionary so can // be reused (e.g. checkMesh -meshQuality) #include "meshQualityDict" // Advanced // Number of error distribution iterations nSmoothScale 4; // amount to scale back displacement at error points errorReduction 0.75; } // Advanced // Merge tolerance. Is fraction of overall bounding box of initial mesh. // Note: the write tolerance needs to be higher than this. mergeTolerance 1e-6; // ************************************************************************* //