Tested with CGX 2.19/ CCX 2.19
Tensile test of a wire of 1 mm diameter made of 1.4301 stainless steel. This steel has a high yield strength but nearly no work hardening, thus the uniform strain is very low and necking occures early and very localized.
The model is axisymmetric and represents a 2 mm piece of the wire with full displacement constraint at one end and symmetry at the other end. Necking occures in the plane of symmetry.
- Large displacements
- Plasticity
- Parametrization alternatives (param.py or CGX valu)
| File | Contents |
|---|---|
| vpre.fbd | Pre-processing script for CGX (parametrized with valu commands) |
| par.pre.fbd | Pre-processing script for CGX (parametrized with param.py) |
| plots.fbd | Post-processing script for CGX (history and path plots) |
| expansion.fbd | Post-processing script for CGX (axisymmetric expansion, plots and movie) |
| 2D.fbd | Post-processing script for CGX (2D display) |
| Zug.inp | CCX input |
| test.py | Test script |
This example is designed with two alternative ways for parametrization. Both produce equivalent results.
The mesh is biased as to account for the localized deformation. Axisymmetric second order quadrilateral elements with reduced integration (CAX8R) are used.
Boundary conditions:
- uy = 0 at y = 0 (symmetry boundary, turquoise)
- uy = 2 at y = 0.3 (displacement controlled extension at the upper edge, blue)
- ux = 0 at x = 0 (restrict nodes to the symmetry axis, green)
The parameters can be changed in pqr.pre.fbd (Parametrization with param.py) or in vpre.fbd (Parametrization with CGX valu).
| Parameter | Value | Meaning |
|---|---|---|
Dia |
1 | diameter in mm |
Len |
2 | (half) length in mm |
Etyp |
qu8cr | element type |
DivL |
50 | longitudinal mesh division |
DivR |
10 | radial mesh division |
BiasL |
4 | longitudinal mesh bias |
See ../../Scripts/ for details
> param.py par.pre.fbd
> cgx -b pre.fbd
> cgx -b vpre.fbd
> ccx Zug
> monitor.py Zug
The second command generates a convergence history plot of the solution.
> cgx -b plots.fbd
This creates path plots of the plastic equivalent strain along the symmetry axis (ine l1 from point cp to point c0) and then in radial direction (line l2 from point c0 to point rad).
The first plot is based on the undeformed geometry:
The second plot is based on the deformed geometry:
Beginning with version 2.10, CGX can sweep 2D elements with results attached. This is used for symmetry expansion of the axisymmetric 2D output.
> cgx -b expansion.fbd
To see just the non-expanded model, use this command:
> cgx -b 2D.fbd
