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


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

Modeling: C_ PLAN.

The structure is a healthy rectangle, in which an interface is introduced directly into the command file using the DEFI_FISS_XFEM [:ref:`U4.82.08 <U4.82.08>`] operator. The interface is present at a distance :math:`{L}_{Y}\mathrm{=}\mathrm{1,8}m` from the top edge of the plate.


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

Number of knots: 661

Number of meshes and types: 200 QUAD8 for the plate and 50 SEG3 for the edges.


.. image:: images/100002010000020F0000031193B4B0EF5C4FCF2B.png
    :width: 2.4102in
    :height: 4.0165in


.. _RefImage_100002010000020F0000031193B4B0EF5C4FCF2B.png:


.. _Ref1542031161:

Figure 3.2‑a: 2D quadrangle mesh and interface position


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

The movements resulting from the operator STAT_NON_LINE are post-processed in order to recover the values at the nodes of the crack from the new mesh.


.. csv-table::

    "**Identification**", "**Reference**", "**Aster**", "**tolerance**"
    ":math:`\mathrm{DX}` at point :math:`A`", "1.10-5", "Analytical", "1.10-12"
    ":math:`\mathrm{DX}` at point :math:`B`", "-1.10-5", "Analytical", "1.10-12"
    ":math:`\mathrm{DY}` at point :math:`A`", "5,52.10-6", "Analytical", "1.10-12"
    ":math:`\mathrm{DY}` at point :math:`B`", "5,52.10-6", "Analytical", "1.10-12"
    ":math:`\mathrm{DY}` at point :math:`O` ", "8,02.10-6", "Analytical", "1.10-12"



Comments
------------

This test validates:


* the calculation of the stiffness matrix and the second member vectors (taking into account the pressure distributed over elements with quadratic edges),


* X- FEM post-processing of :math:`\mathrm{P2}` elements.