Assessment of NUE Fuel Element Performance in Normal Operating Conditions

Due to its neutron economy, versatility of fuel channel and simplicity of fuel bundle design, CANDU reactors have a unique ability of efficiently using alternative fuels, such as: depleted uranium (DU), recycled uranium (RU), mixed oxide of Thorium and Plutonium ((Pu,Th) MOX) and natural uranium equivalent (NUE). This paper outlines the results on the investigation of two analysed cases (NUE versus CANDU standard with 37 fuel elements, 37S) with ELESIM computer code, aimed to evaluate the fuel behaviour in normal operating conditions. ELESIM computer code estimates the nuclear fuel elements performance parameters, for a given history power, using one-dimensional models for heat generation, temperature distribution, fission gas release and pellet to sheath heat transfer. The fuel bundle power distribution for each ring corresponding to a fuel channel was obtained with LEGENTR-3D, WIMS and DRAGON programs. (author).