The cylinder is fixed at one face and a force is acting on the other face in tension.
However, if you naively fixate all three space directions at the one face, you do not get uniaxial stress. So the idea is to let all nodes move freely in the radial direction and fixate them in the tangential and axial direction of the cylinder.
I recall, that calculix offers the TRANSFORM card in order to create a new local coordinate system. While I have confirmed that this works in principle, by editing the input deck file, I can not get it to work via the GUI.
When I select the mesh and click on the transform tool, I select cylindrical.
When then choosing the face to transform, via Add, I get this error message: However, if I select the existing Face in the dialog, I get another error message: I guess now, that the first entry ("select a face") shall be the new coordinate system. So naively I assumed to be the cylindrical bottom. But Calculix requires here an axis vector - so presumably it calculates this via the face normal? Or is that the wrong approach?
Btw, selecting the cylindrical face does not work either. Neither do the cylindrical seam line or the face edge.
Attached is my naive solution.
To get to the correct solution, change the BOUNDARY card to the following:
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*TRANSFORM,NSET=ConstraintFixed,TYPE=C
** Cylindrical coordinate system in the Z axis
0.,0.,0.,0.,0.,1.
** 1 --> radial
** 2 --> tangential
** 3 --> axial
*BOUNDARY
** Not constrained in radial direction
**ConstraintFixed,1
ConstraintFixed,2
ConstraintFixed,3
I thought it might have to do something with the constraining, and also tried a displacement constraint where I predefine the y and z fixed and x free. However, that does also not work.
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OS: Debian GNU/Linux bullseye/sid (i3/i3)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.20310 (Git) AppImage
Build type: Release
Branch: master
Hash: 2cac4898d7d62276fbbaaef5b4cecb9bfdd29a33
Python version: 3.8.2
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: German/Austria (de_AT)