7. E modeling#
7.1. Characteristics of modeling#
We take advantage of the symmetries of the problem to model only one eighth of the sphere.

Three models are tested: AXIS_INCO_UPG (SIMO_MIEHE and GDEF_LOG) and AXIS_INCO_UP
7.2. Characteristics of the mesh#
The 441 node mesh contains 200 TRIA6 elements.
7.3. Tested sizes and results#
The stress trace and the cumulative plastic deformation are tested for the most eccentric and the least eccentric Gauss points.
MODELISATION =” AXIS_INCO_UPG “and DEFORMATION =” SIMO_MIEHE”
Identification |
Reference type |
Reference value |
Tolerance |
Least offset Gauss point - \(\mathit{tr}\sigma\) - Pa |
“ANALYTIQUE” |
-1038055558,5 |
|
Outermost Gauss point - \(\mathit{tr}\sigma\) - Pa |
“ANALYTIQUE” |
287474941.41 |
|
Least offset Gauss point - \(p\) |
“ANALYTIQUE” |
0.095807224561 |
|
Outermost Gauss point - \(p\) |
“ANALYTIQUE” |
4.5056636601e-5 |
|
MODELISATION =” AXIS_INCO_UPG “and DEFORMATION =” GDEF_LOG”
Identification |
Reference type |
Reference value |
Tolerance |
|
Least offset Gauss point - \(\mathit{tr}\sigma\) - Pa |
“ANALYTIQUE” |
-1036113143.5 |
|
|
Outermost Gauss point - \(\mathit{tr}\sigma\) - Pa |
“ANALYTIQUE” |
“” |
287474939.50 |
|
Least offset Gauss point - \(p\) |
“ANALYTIQUE” |
0.096499343842 |
|
|
Outermost Gauss point - \(p\) |
“ANALYTIQUE” |
4.5056643994e-5 |
|
MODELISATION =” AXIS_INCO_UP “and DEFORMATION =” GDEF_LOG”
Identification |
Reference type |
Reference value |
Tolerance |
|
Least offset Gauss point - \(\mathit{tr}\sigma\) - Pa |
“ANALYTIQUE” |
-1036113143.5 |
|
|
Outermost Gauss point - \(\mathit{tr}\sigma\) - Pa |
“ANALYTIQUE” |
“” |
287474939.50 |
|
Least offset Gauss point - \(p\) |
“ANALYTIQUE” |
0.096499343739 |
|
|
Outermost Gauss point - \(p\) |
“ANALYTIQUE” |
4.5056643999e-5 |
|
7.4. notes#
All incompressible formulations give good results. We can see from the that we no longer have oscillations in the value of the stress trace with incompressible formulations unlike standard elements AXIS.

Figure 7.4-a : Trace the constraints in \(\mathit{Mpa}\) for the formulations AXIS , AXIS_INCO **** and the analytical solution**