openfoam/tutorials/mesh/snappyHexMesh/addLayersToFaceZone/system/snappyHexMeshDict
2023-06-28 16:35:48 +01:00

334 lines
10 KiB
C++

/*--------------------------------*- 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;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
// 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;
// Layers defined by overall thickness and expansion ratio
thickness 0.7e-3;
firstLayerThickness 0.1e-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 0.0001e-3;
// Per final patch (so not geometry!) the layer information
layers
{
maxY
{
nSurfaceLayers 3;
}
minY
{
nSurfaceLayers 3;
}
A
{
nSurfaceLayers 3;
}
A_slave
{
nSurfaceLayers 3;
}
}
// 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;
// Optional: at non-patched sides allow mesh to slip if extrusion
// direction makes angle larger than slipFeatureAngle. Default is
// 0.5*featureAngle.
slipFeatureAngle 30;
//// Motion solver instead of default medial axis
//
// //- Use displacementMotionSolver to shrink mesh
// meshShrinker displacementMotionSolver;
//
// //- Use laplacian for shrinking
// solver displacementLaplacian;
//
// displacementLaplacianCoeffs
// {
// diffusivity quadratic inverseDistance ("m.*");
// }
// Mesh shrinking
// 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;
// Overall number of outer layer of iterations. Default is 1 -> all
// layers are added in one pass.
nOuterIter 3;
}
// 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;
debugFlags
(
//mesh
);
// Write flags
writeFlags
(
//layerFields // write volScalarField for layer coverage
);
// ************************************************************************* //