Integrity Analysis of LWR-Components


Dr. Eberhard Altstadt
Dr. Matthias Werner

Fracture mechanical analysis of a thermal shock scenario for a VVER-440 RPV

A pressurized thermal shock (PTS) scenario in a WWER-440 reactor pressure vessel is analyzed. An axial oriented semi-elliptical underclad/surface crack is assumed to be located in the core weld line. Three-dimensional finite element models are used to compute the global transient temperature and stress-strain fields. By using a three-dimensional submodel, which includes the crack, the local crack stress-strain field is obtained. The determination of the stress intensity factor, which is a measure for the loading of the crack, follows the VERLIFE code. With a subsequent post processing using the J-integral technique the stress intensity factors along the crack front are obtained. The results for the underclad and surface crack are compared and discussed under consideration of VERLIFE code.