Predictability of CNEA PHWR MOX Experiments by mean of TRANSURANUS Code, from the IFPE Database

Investigations of fuel behavior are carried out in close connection with experimental research, operation feedback and computational analyses. The comprehensive understanding of fuel rod behavior and accurate prediction of the lifetime in normal operation and in accident conditions are part of the defense in depth concept. In this connection, OECD NEA sets up the public domain database on nuclear fuel performance experiments – International Fuel Performance Experiments (IFPE) database, with the aim of providing a comprehensive and well-qualified database on UO2 fuel with Zr cladding for models development and codes validation. The CNEA’s PHWR MOX Experiment belong to this database. This experiment was carried out in the High Flux Reactor (HFR) of Petten, Holland. It involves six MOX rods prepared and controlled in the CNEA’s “Alpha” Facility (Argentina). The objective of the experiment was to verify the fabrication processes and the study of the fuel behavior with respect to cladding failure due to Stress Corrosion Cracking (SCC) under Pellet Cladding Interaction (PCI) conditions. These rods were irradiated from 0 until 15 MWd/kgU. The code TRANSURANUS version “v1m1j09” is assessed against the database CNEA PHWR MOX in order to verify the capability of the code in predicting the cladding failures due to SCC. Comparisons with the experimental data and the results obtained with BACO code developed by “CNEA” group of Bariloche are presented. Sensitivity calculations are also performed for supporting the analyses of the results, improving the level of understanding of the code capabilities. The main conclusion is that the clad failure propensity of the rods belonging to the PHWR CNEA MOX experiment is conservatively assessed.