Tested with CGX 2.19 / CCX 2.19
- Telescopic structure of linear elastic tubes
- Loaded in pure bending (no shear)
- Surface-to-surface contact
| File | Contents |
|---|---|
| pre.fbd | Pre-processing script for CGX |
| post.fbd | Post-processing script for cgx |
| solve.inp | CCX input |
| moment.plt | Gnuplot input for the moment-time-curve |
| test.py | Python script to run the full simulation |
The tube axis goes along x. The outer tube is fixed at x = 0, the inner tube overlaps with the outer tube by OVL and is loaded with a prescribed rotation at the free end.
The parameters can be changed in pre.fbd.
| Parameter | Value | Meaning |
|---|---|---|
R1 |
50 | radius of the outer tube in mm |
T1 |
5 | wall thickness of the outer tube in mm |
L1 |
500 | length of the outer tube in mm |
R2 |
45 | radius of the inner tube in mm |
T2 |
5 | wall thickness of the inner tube in mm |
TL |
500 | length of the inner tube in mm |
OVL |
150 | overlap in mm |
divt |
2 | mesh division in thickness direction |
divrot |
18 | mesh division in hoop direction |
divl |
100 | mesh division in longitudinal direction |
> cgx -b pre.fbd
The outer end of the inner tube (turquoise) is coupled in x and z direction to the rigid body motion controlled by node 1. This node is constrained in x direction to prevent rigid body motion of the tube and in y direction to prevent free translation of the node in y direction. The load is applied as prescribed rotation about the y axis.
The outer end of the outer tube is fixed (magenta). The nodes in the plane of symmetry (red) are constrained in y-direction.
A non-linear static step with initial increment of 10% is used.
> ccx solve
> monitor.py solve
> cgx -b post.fbd
Equivalent stress
Contact pressure
Moment versus time. Time is proportional to the prescribed rotation. This curve is generated in post.fbd using the commands
> dat2txt.py
> gnuplot moment.plt
