Non-Water Cooled Small Modular Reactor Technologies – Fuel Qualification, Failure Mechanisms and Reactor Service Conditions

Abstract

Several non-water cooled small modular reactor (SMR) designs have recently been proposed to be deployed in Canada. These designs implement new features which may affect how the fuel is qualified for the intended reactor application. That novelty motivated a detailed overview of the role and concept of fuel qualification and their application to non-water cooled SMRs in the context of safety and licensing. From that perspective, current methodologies that are in use or have been recommended for qualifying the fuel of non-water cooled SMR technologies are investigated for two example reactor types. The failure mechanisms of fuel under bounding conditions of normal operation and postulated accident conditions, and the parameters that strongly influence those failures are identified. The correlation between fuel specifications (or fuel property limits), fuel failure mechanisms and reactor service conditions is established as a necessary input to evaluate the margins of safety between fuel design and failure conditions.