7.6 KiB
GMSH
Gmsh is a software for grid generation or meshing for the finite element method. The free software was programmed by Christophe Geuzaine and Jean-François Remacle under the GNU General Public License (GPL) and contains 4 modules:
- a graphics module to create 3-dimensional shapes
- a meshing module
- an equation solver module
- a postprocessor module
Gmsh is considered one of the best 3D file viewers and is used and described scientifically. Gmsh is used after freeCAD & salome to mesh the brep file after export in salome. For better performance, Gmsh should be compiled with openmpi in cluster. After meshing the Mesh is imported to FEA-Tool (as standalone-app or in matlab).
An emacs mode for GMSH and GetDP languages to provide indentation and nice coloring. Add the following lines your emacs configuration file (probably /home/<user>//.emacs.d/init.el): (load "/home/<user>/.emacs.d/path/to/gmsh_getdp.el")
GMSH command line flags
gmsh -<flag> <file>.geoGeometry:
-0
Output model, then exit
-tol value
Set geometrical tolerance (Geometry.Tolerance)
-match
Match geometries and meshes
Mesh:
-1, -2, -3
Perform 1D, 2D or 3D mesh generation, then exit
-format string
Select output mesh format: auto, msh1, msh2, msh22, msh3, msh4, msh40, msh41, msh, unv, vtk, wrl, mail, stl, p3d, mesh, bdf, cgns, med, diff, ir3, inp, ply2, celum, su2, x3d, dat, neu, m, key, off, rad (Mesh.Format)
-bin
Create binary files when possible (Mesh.Binary)
-refine
Perform uniform mesh refinement, then exit
-barycentric_refine
Perform barycentric mesh refinement, then exit
-reclassify angle
Reclassify surface mesh, then exit
-reparam angle
Reparametrize surface mesh, then exit
-part int
Partition after batch mesh generation (Mesh.NbPartitions)
-part_weight [tri,quad,tet,hex,pri,pyr,trih] int
Weight of a triangle/quad/etc. during partitioning (Mesh.Partition[Tri,Quad,…]Weight)
-part_split
Save mesh partitions in separate files (Mesh.PartitionSplitMeshFiles)
-part_[no_]topo
Create the partition topology (Mesh.PartitionCreateTopology)
-part_[no_]ghosts
Create ghost cells (Mesh.PartitionCreateGhostCells)
-part_[no_]physicals
Create physical groups for partitions (Mesh.PartitionCreatePhysicals)
-part_topo_pro
Save the partition topology .pro file (Mesh.PartitionTopologyFile)
-preserve_numbering_msh2
Preserve element numbering in MSH2 format (Mesh.PreserveNumberingMsh2)
-save_all
Save all elements (Mesh.SaveAll)
-save_parametric
Save nodes with their parametric coordinates (Mesh.SaveParametric)
-save_topology
Save model topology (Mesh.SaveTopology)
-algo string
Select mesh algorithm: auto, meshadapt, del2d, front2d, delquad, quadqs, initial2d, del3d, front3d, mmg3d, hxt, initial3d (Mesh.Algorithm and Mesh.Algorithm3D)
-smooth int
Set number of mesh smoothing steps (Mesh.Smoothing)
-order int
Set mesh order (Mesh.ElementOrder)
-optimize[_netgen]
Optimize quality of tetrahedral elements (Mesh.Optimize[Netgen])
-optimize_threshold
Optimize tetrahedral elements that have a quality less than a threshold (Mesh.OptimizeThreshold)
-optimize_ho
Optimize high order meshes (Mesh.HighOrderOptimize)
-ho_[min,max,nlayers]
High-order optimization parameters (Mesh.HighOrderThreshold[Min,Max], Mesh.HighOrderNumLayers)
-clscale value
Set mesh element size factor (Mesh.MeshSizeFactor)
-clmin value
Set minimum mesh element size (Mesh.MeshSizeMin)
-clmax value
Set maximum mesh element size (Mesh.MeshSizeMax)
-clextend value
Extend mesh element sizes from boundaries (Mesh.MeshSizeExtendFromBoundary)
-clcurv value
Compute mesh element size from curvature, with value the target number of elements per 2*pi radians (Mesh.MeshSizeFromCurvature)
-aniso_max value
Set maximum anisotropy for bamg (Mesh.AnisoMax)
-smooth_ratio value
Set smoothing ration between mesh sizes at nodes of a same edge for bamg (Mesh.SmoothRatio)
-epslc1d value
Set accuracy of evaluation of mesh size field for 1D mesh (Mesh.LcIntegrationPrecision)
-swapangle value
Set the threshold angle (in degrees) between two adjacent faces below which a swap is allowed (Mesh.AllowSwapAngle)
-rand value
Set random perturbation factor (Mesh.RandomFactor)
-bgm file
Load background mesh from file
-check
Perform various consistency checks on mesh
-ignore_periocity
Ignore periodic boundaries (Mesh.IgnorePeriodicity)
Post-processing:
-link int
Select link mode between views (PostProcessing.Link)
-combine
Combine views having identical names into multi-time-step views
Solver:
-listen string
Always listen to incoming connection requests (Solver.AlwaysListen) on the given socket (uses Solver.SocketName if not specified)
-minterpreter string
Name of Octave interpreter (Solver.OctaveInterpreter)
-pyinterpreter string
Name of Python interpreter (Solver.OctaveInterpreter)
-run
Run ONELAB solver(s)
Display:
-n
Hide all meshes and post-processing views on startup (View.Visible, Mesh.[Points,Lines,SurfaceEdges,…])
-nodb
Disable double buffering (General.DoubleBuffer)
-numsubedges
Set num of subdivisions for high order element display (Mesh.NumSubEdges)
-fontsize int
Specify the font size for the GUI (General.FontSize)
-theme string
Specify FLTK GUI theme (General.FltkTheme)
-display string
Specify display (General.Display)
-camera
Use camera mode view (General.CameraMode)
-stereo
OpenGL quad-buffered stereo rendering (General.Stereo)
-gamepad
Use gamepad controller if available
Other:
-, -parse_and_exit
Parse input files, then exit
-save
Save output file, then exit
-o file
Specify output file name
-new
Create new model before merge next file
-merge
Merge next files
-open
Open next files
-log filename
Log all messages to filename
-a, -g, -m, -s, -p
Start in automatic, geometry, mesh, solver or post-processing mode (General.InitialModule)
-pid
Print process id on stdout
-watch pattern
Pattern of files to merge as they become available (General.WatchFilePattern)
-bg file
Load background (image or PDF) file (General.BackgroundImageFileName)
-v int
Set verbosity level (General.Verbosity)
-string "string"
Parse command string at startup
-setnumber name value
Set constant, ONELAB or option number name=value
-setstring name value
Set constant, ONELAB or option string name=value
-nopopup
Don’t popup dialog windows in scripts (General.NoPopup)
-noenv
Don’t modify the environment at startup
-nolocale
Don’t modify the locale at startup
-option file
Parse option file at startup
-convert files
Convert files into latest binary formats, then exit
-nt int
Set number of threads (General.NumThreads)
-cpu
Report CPU times for all operations
-version
Show version number
-info
Show detailed version information
-help
Show command line usage
-help_options
Show all options
Convert a gmsh mesh to openfoam
- openFoam mesh conversion/manipulation tools