A LEAST-SQUARE PRINCIPLE FOR THE A POSTERIORI COMPUTATION OF FINITE-ELEMENT APPROXIMATION ERRORS

The contribution supplies a modification and extension of well-known theories for the numerical error estimation. The presented theory is applied to the stress analysis of membrane plates. A least square variational principle is used to formulate a higher order approximation of finite element errors by means of the h- or p-version. The numerical method is applied to individual finite element patches in order to improve stresses and to compute mean errors within these subdomains. Numerical studies with the h-version are presented in comparison to an exact solution of a specific plate problem.