Unstructured T-spline-based Isogeometric Analysis for Thin Shells

doi:10.3901/JME.2018.15.132

Abstract

Abstract: Isogeometric analysis(IGA) is a method aimed at avoiding meshing procedure of the traditional finite element analysis by using the same basis for analysis as is used to describe the geometry, thus integrating CAE into a general CAD modeling system. The unstructured T-splines are adopted to construct complex geometric models. By integrating the Kirchhoff-Love theory, an IGA thin-shell element is established for the modal analysis and elastic analysis. Due to the non-interpolatory nature of the geometric basis functions, the loads of IGA elements cannot be evenly distributed to the control points as with the traditional finite element. The loading areas are then classified to two basic types and an integration mapping method is proposed to map the Gauss quadrature points of the regular domain to the basic types. Numerical examples illustrated that the unstructured T-splines-based thin-shell element could achieve the convergence with much less degrees of freedom than the traditional finite element method and the integration mapping method solves the imposition problem of external loading effectively.

Key words: Bézier extraction, integration mapping, isogeometric analysis, thin-shell, unstructured T-splines

CLC Number:

TP391

YUAN Pei, LIU Zhenyu, QIU Chan, TAN Jianrong. Unstructured T-spline-based Isogeometric Analysis for Thin Shells[J]. Journal of Mechanical Engineering, 2018, 54(15): 132-140.

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