B modeling
==============


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

Plate elements DKT are used


.. image:: images/100040CE000069D500002C8CDB573572E212921F.svg
    :width: 575
    :height: 242


.. _RefImage_100040CE000069D500002C8CDB573572E212921F.svg:

The division is done in the following way:


.. csv-table::

    "We have", "1", "element between :math:`{P}_{1}` and :math:`{P}_{2}`"
    "", "6", "elements between :math:`{P}_{2}` and :math:`{P}_{3}`"
    "", "1", "element between :math:`{P}_{3}` and :math:`{P}_{4}`"
    "", "1", "element between :math:`{P}_{17}` and :math:`{P}_{20}`"
    "", "10", "elements along the sides parallel to :math:`y` (:math:`{P}_{4}{P}_{5}` for example)"


We pass 2 calculations:


* in the first calculation, we establish solid body connections between the lines:


* :math:`{P}_{2}{P}_{7}` and :math:`{P}_{17}{P}_{22}`


* :math:`{P}_{3}{P}_{6}` and :math:`{P}_{18}{P}_{21}`


* :math:`{P}_{10}{P}_{15}` and :math:`{P}_{20}{P}_{23}`


* :math:`{P}_{11}{P}_{14}` and :math:`{P}_{19}{P}_{24}`

via the keyword factor 'LIAISON_COQUE' from the AFFE_CHAR_MECA command.


* in the second calculation, solid body connections are established between the nodes facing each other of the pairs of lines mentioned above via the keyword factor 'LIAISON_SOLIDE' of the AFFE_CHAR_MECA command.


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


.. csv-table::

    "Number of nodes:", "242"
    "Count of elements TRIA3:", "360"



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

The results of the 2 calculations (one with LIAISON_COQUE, the other with LIAISON_SOLIDE) are identical. We will only mention the calculation with LIAISON_COQUE.


.. csv-table::

    "**Clean mode order**", "**Experimental reference**", "**Experimental reference**", "**% difference/finite element model**", "**% difference/finite element model**"
    "7", "606. ", "584. ± 1% ", "610.2", "4.5"
    "8", "760. ", "826. ± 1.5% ", "852.4", "3.2"
    "9", "865. ", "855. ± 1.7% ", "864.8", "1.1"
    "10", "944. ", "911. ± 2% ", "923.9", "1.4"
    "11", "1113. ", "1113. ± 3.6% ", "1110.8", "—0.2"
    "12", "1144. ", "1136. ± 4% ", "1179.5", "3.8"


*average of 5 calculation codes


notes
---------

Calculations made by:


.. code-block:: text

    CALC_MODES
OPTION = 'BANDE',
CALC_FREQ =_F (FREQ = (1.,1200.)),
SOLVEUR_MODAL =_F (METHODE = 'TRI_DIAG',
DIM_SOUS_ESPACE = 12)


Contents of the results file
----------------------------

The first 6 non-zero natural frequencies (eigenvectors and modal parameters).