How does gmsh remove circular midpoints?

[dokken]

Remove save all elements.
I’ve discussed this more in detail in

Read simple gmsh msh using read_from_msh in dolfinx

The reasoning behind @Jesus_Vellojin answer is that dolfinx.io.gmshio uses the GMSH Python API under the hood to extract the cells of interest using the physical groups: It is also written explicitly in the docs: https://docs.fenicsproject.org/dolfinx/v0.7.3/python/generated/dolfinx.io.gmshio.html#dolfinx.io.gmshio.model_to_mesh In general, gmsh doesn’t store un-tagged surfaces, lines, etc, as written in 1.2.3 Elementary entities vs. physical groups It is usually convenient to combine el…

Also, you are not creating a Physical Surface, which you should do.