An improved superconvergent patch recovery technique for the axisymmetrical problems

Abstract The enhancement of the standard post processing technique proposed by Zienkiewicz-Zhu [1] is studied for the axisymmetrical problems using 4-node quadrilateral elements. We have implemented and compared the various a posteriori error estimators in this category. The presented numerical results show that the modification applied to the standard superconvergent patch recovery method improves the reliability of this procedure. As an outcome of our study, the reliability of error estimator based on averaging and extrapolation technique seems indubitably questionable.