5. Internal variables

The internal variables, whose time increments constitute the unknowns of the non-linear system to be solved, are summarized in the Table.

Table 2: Internal variables of model NLH_CSRM

A few additional auxiliary variables appear in the internal variables field in the sense of Code_Aster. These are summarized in the Table.

Table 3: Auxiliary variables for model NLH_CSRM

Note: iniSigTime is not an unknown of the non-linear system to be solved, but it still intervenes in the integration algorithm, i.e. it is not only a post-processing variable. iniSigTime makes it possible to initialize the elastic deformation tensor in case of non-zero initial stresses (but remaining within the initial elasticity domains); this is often the case in geomechanics (example of digging a tunnel). It is therefore necessary to pay particular attention to the initialization of this variable in STAT_NON_LINE and DINA_NON_LINE in case of resumption of calculations.