Fluid Flow Within Hexagonal Lattices

The within-duct assembly region in fast reactors is the fluid space surrounding the fuel pins, within the ducts. We have developed a script to mesh a bare pin hexagonal geometry, with control of the mesh settings (numbers of elements, boundary layer meshing strategy, etc.) and geometry (pin diameter, etc.) by directly editing the script parameters.

Bare Bundle

To generate a mesh for fluid flow such as in Figure 1, you can use the utils/meshes/assembly/mesh.py script.

Figure 1: Example mesh which can be generated with the assembly meshing script

To create the mesh:

cd utils/meshes/assembly/mesh.py
python mesh.py -g

The mesh will be generated with the following sideset IDs:

- 1, fuel pins outer surface - 2, inlet - 3, outlet - 4, hex can wall