CSAR Noon Seminar

Armando Duarte, University of Sao Paulo, Brazil

DATE: Monday, March 17, 2003
TIME: 12:00 Noon
PLACE: 2240 DCL
1304 W. Springfield Ave., Urbana, IL

TITLE: An Overview of Partition of Unity and Generalized Finite Element Methods

Abstract

Several new computational methods proposed in recent years can be cast as a partition of unity method. The key feature of these methods is the use of a partition of unity to build the approximation space. This partition of unity framework has several powerful properties such as the ability to produce seamless hp approximations, the ability to develop customized approximations for specific applications like dynamic crack propagation, the ability to build p-orthotropic approximations on tetrahedral finite element meshes, etc.

In this talk, several applications of partition of unity methods and, in particular, of the generalized finite element method (GFEM) to the solution of solid mechanics problems are shown. In the GFEM, the partition of unity is provided by low order Lagrangian finite element shape functions, linear combinations of these functions or the so-called Shepard functions. In the context of crack simulation, for example, the GFEM method allows for modeling of arbitrary dynamic crack propagation without continuous remeshings or mappings of solutions between consecutive meshes as the crack propagates. Several numerical examples demonstrating the main features and computational efficiency of the GFEM are presented.