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




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

The rotor is modelled by quadratic volume elements (PENTA15 and HEXA20). It is based on two levels having the characteristics given by configuration A above.


.. image:: images/10000200000001DE0000013E85B56F2576FB9E3A.png
    :width: 2.8827in
    :height: 1.6217in


.. _RefImage_10000200000001DE0000013E85B56F2576FB9E3A.png:

Image 3.1-1: Rotor mesh

CALC_MODES calculates the modes specific to standstill (ie. without gyroscopic damping) and at several speeds of rotation, i.e. with gyroscopic damping (option MECA_GYRO), but not taking into account the softening effect caused by centrifugal stiffness (option RIGI_ROTA).




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


.. csv-table::

    "Number of stitches HEXA8 ", "4230"
    "Number of stitches PENTA6 ", "1386"
    "Number of stitches DIS_T ", "2"


**Table** 3.2-1




Results: comparison between Code_Aster and ANSYS calculations
-------------------------------------------------------------

For information purposes, the results of the rotating machine when stopped are given below.


.. csv-table::

    "**Identification**", "**Reference type**", "**Reference value**", "**Tolerance**"
    "Mode 1", "'EXTERNE'", "416.38"," 4.00%"
    "Mode 2", "'EXTERNE'", "416.38"," 4.00%"
    "Mode 3", "'EXTERNE'", "772.65"," 1.00%"
    "Mode 4", "'EXTERNE'", "772.65"," 1.00%"
    "Mode 5", "'EXTERNE'", "1344.3"," 1.00%"
    "Mode 6", "'EXTERNE'", "1344.3"," 1.00%"


**Table** 3.3-1 **: Summary of standstill results**

The tables below give the numerical values tested in this test case. These are the frequencies specific to 100,000 rpm of the rotor supported on its two bearings.


.. csv-table::

    "**Identification**", "**Reference type**", "**Reference value**", "**Tolerance**"
    "Mode 1", "'EXTERNE'", "52.23"," 7.50%"
    "Mode 2", "'EXTERNE'", "175.51"," 1.00%"
    "Mode 3", "'EXTERNE'", "496.09"," 2.00%"
    "Mode 4", "'EXTERNE'", "1032.4"," 1.00%"
    "Fashion 5", "'EXTERNE'", "1824.8"," 6.50%"
    "Mode 6", "'EXTERNE'", "2438.5"," 3.00%"


**Table** 3.3-2 **: Summary of the results tested at the speed of 100,000 rpm**