C modeling
==============


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

The third cut we are testing again corresponds to a case where two of the edges of TETRA10 see the *lsn* cancel out exactly twice, at one of their ends and at their midpoint. An example of this configuration is shown in Figure.


.. image:: images/1000000000000264000002D6E116450B6541F243.jpg
    :width: 4.0882in
    :height: 4.1244in


.. _RefImage_1000000000000264000002D6E116450B6541F243.jpg:

**Figure** 4.1-a **: representation of the C modeling cuta**

For cutting, we come back to the more classical case represented in Figure, whose subtetrahedron cutting is detailed in [:ref:`R7.02.12 <R7.02.12>`].


.. image:: images/1000000000000158000001BBE9806D619BCC662C.jpg
    :width: 3.5835in
    :height: 4.6146in


.. _RefImage_1000000000000158000001BBE9806D619BCC662C.jpg:

**Figure** 4.1-b **: :** **corresponding healthy configuration**


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

To "find yourself" in this cutting configuration, the *lsn* is chosen spherical, with a center C (:math:`-\frac{4}{3}`, :math:`-\frac{4}{3}`, :math:`-\frac{5}{6}`) and with a radius :math:`R=\frac{\sqrt{(249)}}{6}`

The edges of TETRA are then intersected by the *level set* at the following 5 points:


.. csv-table::

    "Intersection point", "Coordinates"
    "IP1 ", "(1,0,0)"
    "IP2 ", "(0.5,0,0.5)"
    "IP3 ", "(0,0.5,0.5)"
    "IP4 ", "(0, :math:`\frac{2\ast \sqrt{(10)}-4}{3}` ,0)"
    "IP5 ", "(:math:`\frac{2\ast \sqrt{(10)}-4}{3}` ,0,0)"



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

After executing command MODI_MODELE_XFEM, we check that the 5 intersection points IP1, IP2,, IP3, IP4 and IP5 are in the group NFISSU and that their position is correct.


.. csv-table::

    "Quantities tested", "Reference type", "Reference value", "Tolerance"
    "COORX IP1 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORY IP1 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP1 ", "'ANALYTIQUE'", "1.0", "10E-06"
    "COORX IP2 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORY IP2 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP2 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORX IP3 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORY IP3 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORZ IP3 ", "'ANALYTIQUE'", "0.5", "10E-06"
    "COORX IP4 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORY IP4 ", "'ANALYTIQUE'", "0.77485177", "10E-06"
    "COORZ IP4 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORX IP5 ", "'ANALYTIQUE'", "0.77485177", "10E-06"
    "COORY IP5 ", "'ANALYTIQUE'", "0.0", "10E-06"
    "COORZ IP5 ", "'ANALYTIQUE'", "0.0", "10E-06"


The cut mesh (Figure) was also post-processed using SALOME. The cut obtained is in accordance with expectations, with 6 subtetrahedra that are consistent with the discontinuity.

.. image:: images/100002010000017B0000022024734A4F2D8CBA8E.png
    :width: 4.5382in
    :height: 4.6272in


.. _RefImage_100002010000017B0000022024734A4F2D8CBA8E.png:


.. image:: images/10000201000001C50000025E74E1472544CBBEF4.png
    :width: 4.5382in
    :height: 4.022in


.. _RefImage_10000201000001C50000025E74E1472544CBBEF4.png:

**Figure** 4.3-a **: C modeling cutting configuration**