Analysis of Reactivity Induced Accident for Control Rods Ejection with Loss of Cooling

TL;DR

This paper numerically analyzes the neutron population behavior during reactivity-induced accidents, specifically control rod ejection with loss of cooling, using the stiffness confinement method to improve safety understanding.

Contribution

It introduces the application of the stiffness confinement method to solve point kinetics equations for reactivity accidents in reactors fueled by uranium and plutonium, including temperature feedback effects.

Findings

Negative temperature feedback helps mitigate accidents.

Control rod ejection causes significant power and temperature pulses.

Results align well with previous studies.

Abstract

Understanding of the time-dependent behavior of the neutron population in nuclear reactor in response to either a planned or unplanned change in the reactor conditions, is a great importance to the safe and reliable operation of the reactor. In the present work, the point kinetics equations are solved numerically using stiffness confinement method (SCM). The solution is applied to the kinetics equations in the presence of different types of reactivities and is compared with different analytical solutions. This method is also used to analyze reactivity induced accidents in two reactors. The first reactor is fueled by uranium and the second is fueled by plutonium. This analysis presents the effect of negative temperature feedback with the addition positive reactivity of control rods to overcome the occurrence of control rod ejection accident and damaging of the reactor. Both power and temperature pulse following the reactivity- initiated accidents are calculated. The results are compared with previous works and satisfactory agreement is found.