.. _V2.02.125:

**v2.02.125** SDLL125 - Rotating beam with 2 disks and 2 non-symmetric bearings subject to gyroscopy
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**Summary:**

This test makes it possible to validate the calculation of the rotation modes of a system of shafts rotating along the axis of rotation :math:`Z` with the CALC_MODE_ROTATION command and to highlight the instability. This validation concerns both positive rotation speeds (modeling A) and negative rotation speeds (modeling B). Modeling C, for its part, validates the consideration of a system of shafts rotating along the axis of rotation :math:`Y`.

In this test, we have a rotor model with two disks, supported by two hydrodynamic bearings, whose stiffness and damping matrices are non-symmetric. This example and the corresponding reference results are taken from the qualification manual for ROTORINSA, [:ref:`bib2 <bib2>`], a finite element software designed to predict the dynamic behavior of rotors under bending.

A good agreement is observed between the Code_Aster results and the reference solution.

.. toctree::
    :hidden:

    self

.. toctree::
    :maxdepth: 2
    :numbered:

    Probl_me_de_r_f_rence
    Solution_de_r_f_rence
    Mod_lisation_A
    Mod_lisation_B
    Mod_lisation_C
    Synth_se_des_r_sultats