Elastic-plastic finite element analyses for the integrity evaluation of nuclear reactor vessel underpressurized thermal shock transients

摘要

In a nuclear power plant, reactor pressure vessel (RPV) is the most important primary pressure boundary ocmponent that must be protected against failure. The neutron irradiation on RPV in the beltline region, however,tends to cause loalized damage accumulation, leading to crack initiation and propagation which raises RPV integrity issues. The objective of this paper is to estimate the integrity of RPV under pressurized thermal shock (PTS) by applying the finite element analysis. In this paper, a parametric study was performed for various crack configurations based on 3-dimensional finite element models. The crack configuration, the crack orientation, the crack aspect models. The crack configuration, the crack orientation, the crack aspect ratio, and the clad thickness were considered int he parametric study. The effect of these parameters on the maximum allowable nil-ductility transition temperatures (RT_NDT) was investigated on the basis of elastic-plastic finite element analyses.