Performance Analysis for Enhanced Cr-coated Fuel Cladding System

Abstract

This study aims to assess the viability of incorporating a coating material, facilitated by an adhesive intermediate layer, into the design of fuel assemblies and reactor cores for the APR1400. This approach aligns with the principles of the accident-tolerant fuel concept, offering enhanced safety and performance characteristics. The material selecting for the coating is Cr with Nb and Mo as an adhesive material for the current Zr fuel-cladding system design. In this study, the potential consequences of evaluating Accident-Tolerant Fuel concepts are examined, with due consideration given to the nuclear reactor core design, operational characteristics, and safety parameters. To maximize the reactor performance, neutronics performance analyses are conducted using stochastic methods. Different Neutronics parameters were investigated at fuel assembly level analysis including the effective multiplication factor, reactivity difference, pin power distributions,239Pu inventory and radial neutron flux during the life cycle. A sensitivity analysis was conducted at the fuel assembly level and within a 2D reactor framework to identify the optimal neutronics performance scenario compared to the conventional Zr cladding material. Furthermore, an analysis of reactivity coefficients was undertaken for the selected scenario, along with equilibrium cycle calculations for the APR-1400 fuel core. A scattered-reloading fuel management scheme has been implemented to achieve the equilibrium cycle and fulfill safety operational criteria, such as maintaining the radial peaking factor below specified safety limits. The equilibrium cycle is attained through consecutive operational cycles, resulting in a consistent pattern of fuel assemblies in a steady-state manner. The outcomes of these analytical endeavors aim to enhance the reactor core performance while simultaneously ensuring adherence to the safety standards prescribed for the APR1400, with a focus on augmenting economic benefits.

Date of Award	4 May 2024
Original language	American English
Supervisor	Saeed Alameri (Supervisor)