Modeling Stress State Stiffening of the Nozzle Zone of Pressure Vessel by Finite Element Method

Structural strength of parts and elements of machines with structural inhomogeneities should in some cases be carried out taking into account the rigidity (type) of their stress-strain state (SSS). The paper presents the implementation of the first two stages of the methodology for assessing the static strength of deformable objects, taking into account the characteristics of the deformation of their material. The essence of these stages is to calculate the stiffness of the finite element model of the structure according to the results of calculating its SSS by the finite element method (FEM). Static calculation of SSS on the FEM of the experimental model of the nozzle zone of the pressure vessel at the time of destruction was performed. Using the calculated characteristics of the SSS at the time of destruction, the rigidity of the SSS was calculated at the nodes and finite elements of the calculation model based on the use of a specially developed computer program with the ability to display the results in the MSC Patran pre-processor.