FERRAMENTA DE MODELAGEM GEOMÉTRICA PARA ANÁLISE ISOGEOMÉTRICA DE COMPÓSITOS LAMINADOS

Resumo

The finite elements method (FEM) is the most commonly used numerical approach for
structural analysis. Recently, the Isogeometric Analysis (IGA) was proposed as an alternative method
to FEM. IGA uses the same functions used in CAD systems in geometric modeling as B-Splines and
Non-Uniform Rational B-Splines (NURBS). Thus, IGA has gained attention by being able to exactly
represent complex geometries due to the use of B-Splines and NURBS in the numerical solution,
eliminating errors caused by geometry approximation present in FEM. NURBS are described by a set
of control points, weights and knot vectors, allowing the representation of both analytical shapes (e.g.
circles, cylinders, and quadrics) and free form models using the same database. However, as the IGA is
more recent than the FEM, there are not many tools to perform isogeometric modeling and analysis.
Therefore, in this paper presents a simple approach for preprocessing isogeometric models based on the
use of a well-known geometric modeler. This program is used for geometry creation and model
refinement using NURBS. These data and the associated attributes (e.g. material, loads and boundary
conditions) are saved in an input file for the analysis program. This preprocessing tool was validated
using of a set benchmarks and very good results were obtained.