Mixed (structured/unstructured) 3D mesh generator with curved cuboid elements (Primitives) based on gmsh

1. Download and install python https://www.python.org/downloads/
2. Install numpy and gmsh packages

pip install -r requirements.txt 

3. Download gmsh_scripts from https://github.com/romanzes637/gmsh_scripts
4. To create mesh use complex_factory.py script

python complex_factory -i [INPUT_FILE]

Input file test_cylinder_simple.json of complex "Cylinder" (axisymmetric multilayer geometry)

{
  "metadata": {
    "type": "class_arguments",
    "class_name": "Cylinder",
    "description": "Test Cylinder simple"
  },
  "arguments": {
    "factory": "geo",
    "radii": [1, 2],
    "heights": [1, 2],
    "layers_lcs": 0.5,
    "volumes_names": ["V1", "V2"],
    "layers_volumes_names": [[0, 1], [0, 1]],
    "transfinite_r_data": [[3, 0, 1], [5, 0, 0.7]],
    "transfinite_h_data": [[3, 0, 1], [9, 1, 3.0]],
    "transfinite_phi_data": [7, 0, 1]
  }
}

File consists of 2 sections: "metadata" and "arguments". Section "metadata" describes type of input file "type", name of a Complex "class_name" and text field "description". Section "arguments" contains input data for Complex "Cylinder":

• "factory" - gmsh kernel: “geo” (default) or “occ” (OpenCascade)
• "radii" - radii of multilayer cylinder: two cylinders with 1 and 2 meters
• "heights" - heights of multilayer cylinder layers: two layers of 1 and 2 meters
• "layers_lcs" - mesh characteristic length
• "volumes_names" - names for mesh volumes
• "layers_volumes_names" - map of volumes names by layers: from bottom to top, from center to side
• "transfinite_r_data" - data for structured mesh by radial layers, [number of nodes, struct type, size rate]. Struct types: 0 - linear, 1 - centered. Size rate is a change of element sizes from center to side
• "transfinite_h_data" - data for structured mesh by height layers. Size rate is from bottom to top
• "transfinite_phi_data" - data for circumferential structured mesh

python complex_factory -i input/test_cylinder_simple.json

python complex_factory -i input/test_cylinder_simple.json -t

python complex_factory -i input/test_cylinder_simple.json -tr

Geuzaine and J.-F. Remacle. Gmsh: a three-dimensional finite element mesh generator with built-in pre- and post-processing facilities. International Journal for Numerical Methods in Engineering 79(11), pp. 1309-1331, 2009

Butov R.A., Drobyishevsky N.I., Moiseenko E.V., Tokarev Yu. N. Mesh generation for radioactive waste management tasks. Radioactive Waste, 2021, no. 1 (14), pp. 87—95. DOI: 10.25283/2587-9707-2021-1-87-95. (In Russian)

Roman Butov

https://github.com/romanzes637

[email protected]