Pin Lattices
The solid pins in fast reactors are cylinders spaced in hexagonal lattices. We have developed a script to mesh this geometry, with control of the mesh settings (numbers of elements, etc.) and geometry (pin diameter, etc.) by directly editing the script parameters.
Bare Bundle
To generate a mesh for solid heat transfer without the wires such as in Figure 1, you can use the utils/meshes/fuel_pins/mesh.py
script.
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Figure 1: Example mesh which can be generated with the fuel_pins
meshing script, shown for 7 assemblies each with 7 pins
To create the mesh: