FSI stability with hex vs. tet elements (OpenFOAM+CalculiX)

Thanks for the reply!

Yes, the case with matching meshes diverges. You’re right, there is no divergence error message. But the CalculiX side gets stuck in calculiation. This is the “never ending simulation” situation that was mentioned in this post. From what I know, this has something to do with divergence, since the residuals and iteration numbers are rising before the “crash” happens.

Fluid-Mesh-Fluid.init.vtk.txt (126.4 KB)Solid-Mesh-Fluid.init.vtk.txt (126.4 KB)
I think the VTK files look okay, though I have problems vizualizing the hexahedron-interfaces with ParaView.

I noticed that the mapping distance is not zero, so there is a slight shift? I haven’t found the source of this yet.

Mapping distance min:0 max:3.06659e-19 avg: 1.16013e-19 var: 1.14503e-38 cnt: 441