Fuel Performance Modelling under LOCA Conditions by TRANSURANUS Code – N. Mihaylov, S. Kalburov, S. Boneva, M. Manolova

The ability to calculate accurately the performance of light water reactor (LWR) fuel rods under long-term irradiation conditions and various operational transients and hypothetical accidents is an important objective of the reactor safety investigations. The IAEA Coordinated Research Project(CRP) FUMAC (Fuel Modelling in Accident Conditions), focuses on the accident conditions and supports the improvement and development of computer modelling codes by compilation and analysis of experimental data for codes validation and for better understanding and enhanced safety of nuclear fuel behavior. The INRNE team participates in this project with simulations and analyses by TRANSURANUS fuel performance code. This report presents the results of simulation of the Halden IFA650.11 experiment with WWER fuel, pre-irradiated up to 56 MWd/kgU and tested under LOCA conditions at Halden.

The goal of this investigation is to study TRANSURANUS code predictions of WWER fuel rods under off-normal conditions (LOCA) and the changes of the fuel rod structure and geometry of fuel and cladding.

Keywords: loss of coolant accident, fuel rod cladding, validation, cladding temperature.