Error Estimation and Adaptivity

Abstract

A review of stress computation methods is presented for finite element displacement models. They include an original stress smoothing method. called "averaging + extrapolation". based on the idea of "optimal stress extrapolation points"; it is valid for general two dimensional meshes composed of iso-parametric elements of degree up to three. 1be smoothed stress field is used to derive an a posteriori error estimator measured in the energy norm. Numerical examples in plane elasticity are
presented to show the reliability of the error estimator and to introduce its use in adaptive meshing.