3D problems analysis using recovery stress

In this work it is presented the application of the smoothed stress field improved techniques for superconvergent patch recovered (SPR) and recovery by equilibrium in patches (REP) on hexahedrons in problems with three-dimensional domain that allows to obtain more precise results when using the method of the finite elements. In order to analyze the behavior of each technique separately, a h_adaptative procedure is given, where the estimator of Zienkiewicz-Zhu error (z²) is used for the estimation of the error that involves the stress range improved. In this, the effectiveness index for problems with smooth solution and cases where the solution is singular are analyzed. The obtained results show that both techniques are computationally analogous when the meshes have elevated degrees of freedom (dof), also it is observed a similar behavior when the effectiveness index is analyzed.