Uncertainty analysis of important parameters that characterize nuclear fuel behavior during accident conditions
were performed using the TRANSURANUS code. The possible values of these parameters during transients in the fuel vicinity
were evaluated. The most critical among the parameters are presented by means of fractional frequency in this paper. The
obtained results are in good agreement with the experimental values measured in the IFA 650 LOCA experiments in Halden
Research Reactor.
Keywords: TRANSURANUS fuel modelling, WWER fuel, fuel behavior, nuclear safety, uncertainty analysis, Monte Carlo
simulation.