Modeling A
==============


Characteristics of modeling A
-------------------------------------


.. image:: images/10000000000001A900000166A633CE2175358E79.jpg
    :width: 3.0091in
    :height: 2.5217in


.. _RefImage_10000000000001A900000166A633CE2175358E79.jpg:

**Figure 3.1-** 3.1-a

Only a quarter of a plate is modelled. Symmetry conditions are introduced on the two faces shown above.

In addition, all the edge nodes located halfway through are fixed at :math:`x,y,z`.

In order to represent the thin shell hypotheses as accurately as possible, linear constraints are introduced on the degrees of freedom of the edge nodes. These are written:

for two nodes :math:`i` and :math:`j` located on either side of the middle sheet:

:math:`{u}_{i}+{u}_{j}=0`

:math:`{v}_{i}+{v}_{j}=0`

where u and v designate the movements along the axes :math:`x` and :math:`y`.

The follower pressure is applied linearly using 6 increments.


Characteristics of the mesh
----------------------------


.. csv-table::

    "Number of nodes:", "2091"
    "Number of meshes and types:", "368 HEXA20, 28 PENTA15"
    "", "92 QUAD8, 7 TRIA6"



Tested values
---------------


.. csv-table::

    "**Identification**", "**Reference**"
    "", ""
    "Arrow :math:`\mathrm{w0}` :math:`(\mathrm{mm})` ", "—1.441838E—3"
    "SIXX :math:`(\mathrm{MPa})` center, half—thickness", "3850.9"
    "SIYY :math:`(\mathrm{MPa})` center, half—thickness", "3850.9"
    "SIXX :math:`(\mathrm{MPa})` center, lower skin", "8133.6"
    "SIYY :math:`(\mathrm{MPa})` center, lower skin", "8133.6"
    "SIXX :math:`(\mathrm{MPa})` :math:`r=R/2`, half—thickness", "3512.8"
    "SIYY :math:`(\mathrm{MPa})` :math:`r=R/2`, half—thickness", "2947.5"
    "SIXX :math:`(\mathrm{MPa})` :math:`r=R/2`, lower skin", "7815.7"
    "SIYY :math:`(\mathrm{MPa})` :math:`r=R/2`, lower skin", "7307.0"



notes
---------

The same precision on the results is obtained using a single loading increment.