Automated Generation of F.E.A Models Through Idealization Operators

2nd Symposium on Trends in Unstructured Mesh Generation, University of Colorado, Boulder, August 1999

MESHING
RESEARCH
CORNER

Laboratoire Sols, Solides, Structures UMR-CNRS 5521, BP 53 38041 Grenoble Cedex, France
Lionel.Fine@hmg.inpg.fr

Abstract
The use of Finite Element Analysis (F.E.A) during a design process is often restricted to validation phases because of the time needed to generate the mechanical model used for an analysis. Indeed, the generation of F.E.A. models needs a significant expertise from engineers to avoid computer resources to be wasted. To save engineers time, such models ought to be generated as automatically as possible. To this end, automatic processes that generate meshes directly from CAD data are more and more incorporated into F.E. softwares. These idealizations are carried out through a vertex removal process which transforms geometry of a part according to a discrete envelope defined around its initial geometry[4]. This envelope is generated from a mechanical criterion which can be based either on an a posteriori error estimator [5][6] or on a priori estimation. The use of this criterion ensures that all geometric transformations which keep the geometry of the part within this envelope do not significantly change the results of the F.E.A. More than strictly respecting this envelop, operators used for idealization are also able to transfer specific data (like boundary conditions) from initial to idealized geometry. Such operators allow a broader automation of geometry simplification and idealization and ensure that the new geometry is more suited to the element size requirements attached to the mesh generation process.

The insertion of mechanical criteria into the process of geometry adaption, as presented in this paper, adds flexibility to F.E.A. tools, thus improving their integration into the design process. This approach is illustrated and validated through an example.

References

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