Hi, everyone!
I have this script (attached) where a block of a hyperelastic, "almost incompressible", material is deformed uniformly. The results seem acceptable with coarse meshes (e.g. N_NODES=3, lo_mesh.png), but weird things show up with finer ones (N_NODES=10, hi_mesh.png).
I've tried tweaking some solvers settings (e.g. changing i_max or
eps_r etc. or switching to ScipyIterative linear solver), which
led to some minor changes, but did not actually solve the problem.
Can this be due to the solvers setting?
Or is it a property of the displacement-based formulation? (i.e. would
mixed formulation work better?)
I also noted that the example
large_deformation/compare_elastic_materials.py seems to converge
reliably, but loading is imposed by surface tractions instead of
prescribed displacements in it.
Thanks, Jan
