Nonlinear dynamic analysis of nuclear fuels considering thermo–elastic–plastic–creep phenomena

Abstract

Recently, research on the behavior of nuclear fuel rods in accident situations was performed. The research conducted was very sophisticated and involved complex tasks related to thermal, elastic, plastic, and creep phenomena. Previously, a nonlinear iterative static analysis for the behavior of a nuclear fuel rod was performed taking into consideration the thermal, elastic, plastic, and creep effects. However, the analysis cannot be applied to an unstable situation such as a bulging phenomenon of a nuclear fuel rod when a loss of coolant accident occurs. In this study, a nonlinear iterative dynamic analysis is performed considering large strain and thermo-mechanical effects, and the results of this dynamic analysis were obtained. The analysis is similar to those of static analysis; however, it differs from the static analysis after loss of coolant accident because of the inertia term of the dynamic equation.