Preprocess

Generate STL patch mesh

Boundaries may be specified with the surfaceToPatch utility in OpenFOAM, based on STL files that can be generated with

python applications/write_stl_patch.py -v

The verbose flag (-v) generates a plot of the stl mesh (as shown below)

STL patch

How to change the set of shapes in the boundary patch?

Edit the json files that are read when generating the mesh. In the case tutorial_cases/loop_reactor_mixing, the boundary condition inlets consists of 3 discs

{
    "inlets": [
        {"type": "circle", "centx": 5.0, "centy": 0.0, "centz": 0.5, "radius": 0.4, "normal_dir": 1,"nelements": 50},
        {"type": "circle", "centx": 2.5, "centy": 0.0, "centz": 0.5, "radius": 0.4, "normal_dir": 1,"nelements": 50},
        {"type": "circle", "centx": 7.5, "centy": 0.0, "centz": 0.5, "radius": 0.4, "normal_dir": 1,"nelements": 50}
    ],
}