The use of finite element analysis during a design process is often restricted to validation phases because of the time needed to prepare the data and the geometric representation of the analysis model and to generate an appropriate FE mesh. Such input models may require substantial simplifications of their geometry when it incorporates many geometric aspects related to the technology of its manufacturing process. Here, polyhedrons are used as input geometric representation for geometry adaptation purposes because of their significant freedom for shape modifications. Geometric adaptation operations performing topological changes are described to produce functions capable of removing through holes which represent frequently details in analysis models. The proposed approach fits into an automatic process of localisation of through holes in a polyhedron. This localisation process is based on a decimation process of the polyhedron which repeatedly removes vertices according to geometric criteria. When the decimation process has reduced holes to specific schemes in the polyhedron, topological criteria are used to locate unambiguously the faces defining the through holes. Then, hole removal operators are triggered to effectively remove set of faces which define the holes. Specific treatments are also described which can be used to locate and identify through holes with complex contour curves, namely holes with non convex sections. Again, these treatments are based on topological criteria as well as on the decimation process controlled through new vertex selection criteria. All this localisation and detail removal process is controlled through user defined data which characterises explicitly the relevant details of a FE analysis. This input data can be expressed a priori by the user based on his (resp. her) know-how or automatically deduced from a posteriori error estimators. Finally, examples are given which illustrate the behaviour of operators described.

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