Tested with CGX 2.19 / CCX 2.19
- Axisymmetric model
- Linear elasticity
- Surface-to-surface Penalty contact
- Force (pressure) control
| File | Contents |
|---|---|
| pre.fbd | Pre-processing script for CGX (parametrized with valu) |
| Hertz.inp | CCX input, surface-to-surface penalty contact |
| post.fbd | CGX post-processing script |
| plots.fbd | CGX post-processing script (path plots) |
| plots.gnu | Gnuplot script for path plots |
| test.py | Python script to run the full simulation |
The parameters can be changed in pre.fbd.
| Parameter | Value | Meaning |
|---|---|---|
radius |
50 | radius of the hemisphere in mm |
height |
60 | thickness of the cylindrical disk in mm |
width |
120 | radius of the cylindrical disk in mm |
etyp |
qu8c | element type (in CGX terms) |
Two separate parts are generated and meshed with axisymmetric elements (by default CAX8). The load is applied as pressure to the flat equatorial surface of the hemisphere (blue). The lower surface of the flat disk (red) is constrained in axial (y) direction. The nodes on the axis of symmetry (magenta) are constrained in radial (x) direction.
> cgx -b pre.fbd
> ccx Hertz
> monitor.py Hertz
As you see, the force control is quite challenging for the solver.
> cgx -b post.fbd
The solution shows the expected feature of Hertz contact with the maximum of the equivalent stress somewhat below the contact surface. However, there is evidence of contact finding problems near the axis of symmetry. With CAX8R elements (reduced integration, specify qu8cr in pre.fbd) this problem is even more pronounced.
> cgx -b plots.fbd
Stress plot along the axis of symmetry (x=0) at the contact location:
Contact pressure distribution along the meridian of the sphere:
