/*--------------------------------*- C++ -*----------------------------------*\ | ========= | | | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | | \\ / O peration | Version: 1.6 | | \\ / 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; 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 { motorBike.stl { type triSurfaceMesh; name motorBike; } refinementBox { type searchableBox; min (-1.0 -0.7 0.0); max ( 8.0 0.7 2.5); } }; // 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 1000000; // 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 3; // 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 "someLine.eMesh"; // level 2; //} ); // 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 { motorBike { // 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 { refinementBox { 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 (3 3 0.43); } // 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; //- 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 true; // Per final patch (so not geometry!) the layer information layers { minZ { nSurfaceLayers 1; } motorBike_frt-fairing:001%1 { nSurfaceLayers 1; } motorBike_windshield:002%2 { nSurfaceLayers 1; } motorBike_rr-wh-rim:005%5 { nSurfaceLayers 1; } motorBike_rr-wh-rim:010%10 { nSurfaceLayers 1; } motorBike_fr-wh-rim:011%11 { nSurfaceLayers 1; } motorBike_fr-wh-brake-disk:012%12 { nSurfaceLayers 1; } motorBike_frame:016-shadow%13 { nSurfaceLayers 1; } motorBike_rear-susp:014%14 { nSurfaceLayers 1; } motorBike_rear-susp:014-shadow%15 { nSurfaceLayers 1; } motorBike_frame:016%16 { nSurfaceLayers 1; } motorBike_rr-wh-rim:005-shadow%17 { nSurfaceLayers 1; } motorBike_rr-wh-chain-hub:022%22 { nSurfaceLayers 1; } motorBike_rearseat%24 { nSurfaceLayers 1; } motorBike_frt-fairing%25 { nSurfaceLayers 1; } motorBike_windshield%26 { nSurfaceLayers 1; } motorBike_headlights%27 { nSurfaceLayers 1; } motorBike_driversseat%28 { nSurfaceLayers 1; } motorBike_rear-body%29 { nSurfaceLayers 1; } motorBike_fuel-tank%30 { nSurfaceLayers 1; } motorBike_exhaust%31 { nSurfaceLayers 1; } motorBike_rr-wh-rim%32 { nSurfaceLayers 1; } motorBike_fr-mud-guard%33 { nSurfaceLayers 1; } motorBike_fr-wh-rim%34 { nSurfaceLayers 1; } motorBike_fr-wh-brake-disk%35 { nSurfaceLayers 1; } motorBike_fr-brake-caliper%36 { nSurfaceLayers 1; } motorBike_fr-wh-tyre%37 { nSurfaceLayers 1; } motorBike_hbars%38 { nSurfaceLayers 1; } motorBike_fr-forks%39 { nSurfaceLayers 1; } motorBike_chain%40 { nSurfaceLayers 1; } motorBike_rr-wh-tyre%41 { nSurfaceLayers 1; } motorBike_square-dial%42 { nSurfaceLayers 1; } motorBike_round-dial%43 { nSurfaceLayers 1; } motorBike_dial-holder%44 { nSurfaceLayers 1; } motorBike_rear-susp%45 { nSurfaceLayers 1; } motorBike_rear-brake-lights%46 { nSurfaceLayers 1; } motorBike_rear-light-bracket%47 { nSurfaceLayers 1; } motorBike_frame%48 { nSurfaceLayers 1; } motorBike_rear-mud-guard%49 { nSurfaceLayers 1; } motorBike_rear-susp-spring-damp%50 { nSurfaceLayers 1; } motorBike_fairing-inner-plate%51 { nSurfaceLayers 1; } motorBike_clutch-housing%52 { nSurfaceLayers 1; } motorBike_radiator%53 { nSurfaceLayers 1; } motorBike_water-pipe%54 { nSurfaceLayers 1; } motorBike_water-pump%55 { nSurfaceLayers 1; } motorBike_engine%56 { nSurfaceLayers 1; } motorBike_rear-shock-link%57 { nSurfaceLayers 1; } motorBike_rear-brake-fluid-pot-bracket%58 { nSurfaceLayers 1; } motorBike_rear-brake-fluid-pot%59 { nSurfaceLayers 1; } motorBike_footpeg%60 { nSurfaceLayers 1; } motorBike_rr-wh-chain-hub%61 { nSurfaceLayers 1; } motorBike_rear-brake-caliper%62 { nSurfaceLayers 1; } motorBike_rider-helmet%65 { nSurfaceLayers 1; } motorBike_rider-visor%66 { nSurfaceLayers 1; } motorBike_rider-boots%67 { nSurfaceLayers 1; } motorBike_rider-gloves%68 { nSurfaceLayers 1; } motorBike_rider-body%69 { nSurfaceLayers 1; } motorBike_frame:0%70 { nSurfaceLayers 1; } motorBike_frt-fairing:001-shadow%74 { nSurfaceLayers 1; } motorBike_windshield-shadow%75 { nSurfaceLayers 1; } motorBike_fr-mud-guard-shadow%81 { nSurfaceLayers 1; } motorBike_fr-wh-brake-disk-shadow%83 { nSurfaceLayers 1; } motorBike_rear-mud-guard-shadow%84 { nSurfaceLayers 1; } motorBike_rear-susp-spring-damp-shadow%85 { nSurfaceLayers 1; } motorBike_radiator-shadow%86 { nSurfaceLayers 1; } motorBike_rear-shock-link-shadow%87 { nSurfaceLayers 1; } motorBike_rear-brake-fluid-pot-bracket-shadow%88 { nSurfaceLayers 1; } motorBike_rr-wh-chain-hub-shadow%89 { nSurfaceLayers 1; } } // 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. // 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. nGrow 1; // Advanced settings //- When not to extrude surface. 0 is flat surface, 90 is when two faces // make straight angle. 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 minMedianAxisAngle 130; // Create buffer region for new layer terminations nBufferCellsNoExtrude 0; // Overall max number of layer addition iterations 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 projected area v.s. actual area. Set to -1 to disable. minFlatness 0.5; //- 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 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 0.02; //- minimum normalised cell determinant //- 1 = hex, <= 0 = folded or flattened illegal cell minDeterminant 0.001; //- minFaceWeight (0 -> 0.5) minFaceWeight 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 // Flags for optional output // 0 : only write final meshes // 1 : write intermediate meshes // 2 : write volScalarField with cellLevel for postprocessing // 4 : write current intersections as .obj files 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; // ************************************************************************* //