Development of the FAST Code for Modeling CANDU Fuel

Abstract

The Fuel And Sheath modelling Tool (FAST) is a general purpose fuel performance code for normal operating conditions developed at RMC. FAST includes models for heat generation and transport, thermal-expansion, elastic strain, densification, fission product swelling, contact, grain growth, fission gas release, gas and coolant pressure and sheath creep. These models have been coupled together using the Comsol platform and are solved on a quarter cross-section of a fuel pellet and sheath in two dimensions (radial-axial). FAST has undergone a preliminary validation against experimental post-irradiation data from six fuel elements and comparison to the ELESTRES-IST and ELESIM fuel performance codes. The results show excellent agreement with experimental measurements and other codes.