I tried to define the regions for my BCs using nodal sets, i.e. I would like to select different portions of the surface of my domain.
I was almost able to do it using nodal sets in the Abaqus (.inp) mesh format. Here is my testing file:
Abaqus DataFile Version 6.14
written by meshio v5.3.0
1, 0.0000000000000000e+00, 0.0000000000000000e+00, 0.0000000000000000e+00
2, 1.0000000000000000e+00, 0.0000000000000000e+00, 0.0000000000000000e+00
3, 0.0000000000000000e+00, 1.0000000000000000e+00, 0.0000000000000000e+00
4, 1.0000000000000000e+00, 1.0000000000000000e+00, 0.0000000000000000e+00
5, 0.0000000000000000e+00, 0.0000000000000000e+00, 1.0000000000000000e+00
6, 1.0000000000000000e+00, 0.0000000000000000e+00, 1.0000000000000000e+00
7, 0.0000000000000000e+00, 1.0000000000000000e+00, 1.0000000000000000e+00
8, 1.0000000000000000e+00, 1.0000000000000000e+00, 1.0000000000000000e+00
Now if I try to define a region by 'vertices of set 1' I get 'ValueError: undefined vertex set! (1)'. It seems to me that only some previously defined regions are considered in this case.
If I define it by 'vertices of group 0', the regions are defined without an error, but do not contain the correct vertices (top: [4 5 6 7], bottom: [0 1 2 3] - i.e. four nodes are missing from the `bottom` region). I traced this down to `MeshioLibIO.read` (lines 385-394), where sets (`m.point_sets`, which contain the correct nodes) are converted into groups (`ngroups`, only one group per node).
Is there some way how to make this work?