Utilizing the IRF for CANDU Fuel Bundle Irradiations

Abstract

This paper reports a design study of power and reactivity trade-offs for the expected range of CANDU bundles that will be tested in AECL's new Irradiation Research Facility (IRF). The study tracked peak driver-fuel ratings, test-fuel bundle powers and ratings as a function of burnup, and excess reactivity relative to the reference configuration of nine natural 37-element bundles (three per channel) with a uniform burnup of 3.5 MWd/kgU. The driver-fuel burnup distribution represented "Day 2" of an IRF operating cycle. The study provides a first-order parametric assessment of HTF behaviour, and establishes the need for lower-flux HTF positions that will limit the power of low-burnup, high-fissile-content test bundles to acceptable levels.