.. _R7.02.01:

**r7.02.01** Rate of energy release in linear thermoelasticity
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**Summary:**

The calculation of the energy restoration rate :math:`G` by the :math:`\theta` method is presented in 2D or 3D for a linear thermo-elastic problem. We explain how field :math:`\theta` is introduced and how the energy return rate is calculated with the CALC_G operator.

Mechano-reliable studies to assess the probability of the rupture initiating, in addition, require its derivative with respect to a domain variation driven by another field. The implementation of this option in the code is detailed.

The calculation of :math:`G` is available both for a meshed crack (classical finite elements) and for a non-meshed crack (enriched finite elements: method X- FEM). The calculation of its derivative is only available in 2D, for a meshed crack.






.. toctree::
    :hidden:

    self

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

    Calcul_du_taux_de_restitution_d__nergie_par_la_m_thode__math___theta_en_thermo-_lasticit__lin_aire
    Discr_tisation_du_taux_de_restitution_d__nergie
    Introduction_du_champ__math___theta_
    Bibliographie