songtianlun/openfoam
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ENH: flange: run snappyHexMesh to add layers

Browse Source
This commit is contained in:
mattijs 2012-03-30 16:02:47 +01:00
parent 6757a6b70d
commit 143b4b7039
3 changed files with 396 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
tutorials/mesh/cvMesh/flange/system/cvMeshDict
View File

@ -113,7 +113,7 @@ initialPoints
minimumSurfaceDistanceCoeff 0.55;
initialPointsMethod autoDensity;
// initialPointsMethod pointFile;
//initialPointsMethod pointFile;
autoDensityCoeffs
{
@ -143,10 +143,15 @@ motionControl
{
priority 1;
mode inside;
surfaceCellSizeFunction uniformValue;
uniformValueCoeffs
{
surfaceCellSize 0.0005;
}
cellSizeFunction linearDistance;
linearDistanceCoeffs
{
surfaceCellSize 0.0005;
distanceCellSize $defaultCellSize;
distance 0.004;
}
@ -205,27 +210,14 @@ polyMeshFiltering
filterCountSkipThreshold 4;
maxCollapseIterations 25;
maxConsecutiveEqualFaceSets 5;
surfaceStepFaceAngle 80;
edgeCollapseGuardFraction 0.3;
surfaceStepFaceAngle 90;
edgeCollapseGuardFraction 0.0; //0.3;
maxCollapseFaceToPointSideLengthCoeff 0.35;
edgeMergeAngle 30;
}
meshQualityControls
{
maxNonOrtho 65;
maxBoundarySkewness 50;
maxInternalSkewness 10;
maxConcave 80;
minTetQuality 1e-30;
minVol 0;
minArea -1;
minTwist 0.001;
minDeterminant 0.001;
minFaceWeight 0.02;
minVolRatio 0.01;
minTriangleTwist -1;
}
#include "meshQualityControls"
// ************************************************************************* //

76
tutorials/mesh/cvMesh/flange/system/meshQualityControls Normal file
View File

@ -0,0 +1,76 @@
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: dev |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
root "";
case "";
instance "";
local "";
class dictionary;
object meshQualityControls;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
meshQualityControls
{
//- Maximum non-orthogonality allowed. Set to 180 to disable.
maxNonOrtho 65;
//- Max skewness allowed. Set to <0 to disable.
maxBoundarySkewness 50;
maxInternalSkewness 10;
//- 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 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 1e-30;
//- 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 0;
//- 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 0.001;
//- 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;
}
// ************************************************************************* //

309
tutorials/mesh/cvMesh/flange/system/snappyHexMeshDict Normal file
View File

@ -0,0 +1,309 @@
/*--------------------------------*- C++ -*----------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: dev |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ 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.
// 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.obj
// {
// 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 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 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);
//
// // Optional specification of patch type (default is wall). No
// // constraint types (cyclic, symmetry) etc. are allowed.
// patchInfo
// {
// type wall;
// inGroups (motorBike);
// }
// }
}
// 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 (-1 0 0);
// 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 4.0;
//- Number of mesh displacement relaxation iterations.
nSolveIter 0;
//- Maximum number of snapping relaxation iterations. Should stop
// before upon reaching a correct mesh.
nRelaxIter 5;
//- Highly experimental and wip: number of feature edge snapping
// iterations. Leave out altogether to disable.
// Do not use here since mesh resolution too low and baffles present
//nFeatureSnapIter 10;
}
// 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;
// Per final patch (so not geometry!) the layer information
layers
{
"flange.obj.*"
{
nSurfaceLayers 1;
}
}
// Expansion factor for layer mesh
expansionRatio 1.5;
//- 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 0.0003;
//- 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 0.0001;
//- 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
// make straight angle.
featureAngle 90;
//- 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 1000;
// 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.
#include "meshQualityControls"
meshQualityControls
{
//- 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;
// ************************************************************************* //