6. Summary of results#

In this test case, it is a question of ensuring the non-regression of TP 1 associated with the courses « Error indicators and mesh adaptation; State of the art and implementation in Code_Aster » of the « Nonlinear static analysis with Code_Aster »* course of the « Nonlinear static analysis with Code_Aster » course.

In fact, we « manhandle » an elastic calculation on a bending metal beam in plane stress modeling. It is converged uniformly via the refinement-deraffing tool HOMARD encapsulated in MACR_ADAP_MAIL, then freely by coupling the process to a spatial error map located on each finite element.

The objectives of this TP are multiple, they are:

  • to become familiar with and put into practice the two dual problems: error indicator map calculation and mesh adaptation strategies. On standard cases, but also on pathological cases…,

  • to detail the various settings of the offending operators (CALC_ERREUR, MACR_ADAP_MAIL) and related operators that may be particularly interesting for these problems (INFO_MAILLAGE, MACR_INFO_MAIL, PROJ_CHAMP…),

  • to hammer out « good practice » advice for the quality of studies and the use of tools already available on the subject. We are only interested in aspects such as mesh geometry, meshing itself and the type of finite elements. We do not focus here on the problems of time steps, the calibration of numerical parameters and on the sensitivity aspects with respect to the data,

  • to illustrate the great possibilities and facilities that the « language ASTER/PYTHON » coupling allows in the command file of a study (test, loop, display, calculation, calculation, personal macro-command, interactivity…). Since the official test cases are calibrated to work in batch, some of these aspects have therefore been « commented » in the command file.

From a computer validation point of view, this test case makes it possible of course to test the non-regression of various combinations (error map calculations/refinement-deraffing procedure) in mechanics, but also the « pre and post-processing » options for these calculations (smoothing the constraints at the nodes, transition from an error per element to an error at the nodes per element).

Each modeling is associated with a TP question and we transcribed the « substantial » core of the correction elements. The full text of the TP is available on the website http://www.code-aster.com/utilisation/formations.