Modeling I
==============


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

We use a AXIS model (quadratic elements).


.. image:: images/Object_18.svg
    :width: 484
    :height: 259


.. _RefImage_Object_18.svg:

The continuous contact formulation is used. This test case is used to validate the CONTACT_INIT = 'INTERPENETRE' feature. Here we use the GLISSIERE function, which makes it possible to maintain contact throughout the extrusion, mathematically. The result is physically similar to modeling without a slide, since it is a frictionless extrusion.


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


.. image:: images/Object_19.png
    :width: 5.5201in
    :height: 1.5209in


.. _RefImage_Object_19.png:

Number of knots: 1174

Number of meshes: 510 TRIA6 and 152 SEG3

Number of nodes in contact: 38


Tested sizes and results
------------------------------

The reference values are considered to be those of the C modeling.

The following displacement :math:`Y` of the point :math:`K` of the piece of paper with respect to the surface :math:`\mathrm{ABCDEFG}` of the die is tested.

.. csv-table::

    "**Identification**", "**Reference type**", "**Reference value**", "**Tolerance**"
    "Point :math:`K`/Point :math:`B` - :math:`\mathrm{DY}` ", "'ANALYTIQUE'", "5.0000"," 0.1%"
    "Point :math:`K`/Point :math:`F` - :math:`\mathrm{DY}` ", "'NON_REGRESSION'", "144.9480"," 0.1%"



notes
---------

The calculation is carried out by imposing a displacement on the back side of the block :math:`\text{(MN)}`. The displacement is imposed as follows:


.. csv-table::

    "* from", ":math:`\mathrm{0.mm}` to", ":math:`\mathrm{5.mm}` in 5 steps"
    "* from", ":math:`\mathrm{5.mm}` to", ":math:`\mathrm{20.mm}` in 15 steps"
    "* from", ":math:`\mathrm{20.mm}` to", ":math:`\mathrm{50.mm}` in 10 steps"
    "* from", ":math:`\mathrm{50.mm}` to", ":math:`\mathrm{70.mm}` in 10 steps"
    "* from", ":math:`\mathrm{70.mm}` to", ":math:`\mathrm{140.mm}` in 35 steps"
    "* from", ":math:`\mathrm{140.mm}` to", ":math:`\mathrm{155.mm}` in 15 steps"


The calculations do not converge with the default keywords used for convergence in STAT_NON_LINE, because the default value of RESI_GLOB_RELA = 1.E-6 is too restrictive (the forces to which the piece is subjected are initially relatively weak). To overcome this problem, use the keyword RESI_GLOB_MAXI = 1.E-6.