A Coupled Isogeometric Analysis and Finite Element Approach for Accurate Response Prediction of a Complex Structure

摘要

A critical step in the isogeometric analysis (IGA) is to create a finite element model that employs the same spline functions used in the geometric model of CAD drawings. While advanced T-spline modeling techniques have been developed to enhance the modeling capability for a complex 3D geometry, it still cannot be generalized to an arbitrary complex geometry. Sometimes, it is not always feasible to convert a complex CAD model to pure volumetric NURBS/T-splines. Building an all-hex control mesh and preserving all detailed features can be extremely hard, especially for some sharp features. Given that the CAD tools currently lack the capability to create an analysis suitable T-spline model for a 3D geometry, a rational modeling approach based on the IGA enriched Bezier element for a commercial finite element software such as Abaqus is developed by combining IGA basis functions with traditional piecewise linear finite element basis functions The essential feature of this hybrid approach includes the application of IGA elements for the surface layer of a complex geometry and the use of a conventional finite element mesh for its interior region. An incompatibility between the kinematic description of the surface layer and the interior regions is captured by using the IGA enriched Bezier elements. After the verification at element level, the applicability of the hybrid approach based on the IGA enriched Bezier element is demonstrated via the response prediction of a 3D mechanical component.