RELAP5/MOD3.2 Analysis of a VVER-1000 Reactor with UO₂ Fuel and Mixed-Oxide Fuel

A RELAP5/MOD3.2 model of the VVER-1000/MODEL V320 nuclear power plant was modified and a large-break loss-of-coolant accident (LBLOCA) in the cold leg was simulated. In this analysis, the core consisted of 162 UO₂ assemblies and 1 mixed-oxide assembly. The results from the simulation were compared with the results from a similar study performed with the Russian computer program TECH-M. An uncertainty analysis was performed on the peak cladding temperature following a similar methodology called code scaling, applicability, and uncertainty. Monte Carlo calculations were performed using the response surface inferred from 15 runs of RELAP5 calculations. The result of this study shows that the emergency core coolant system would be sufficient to keep the cladding temperature during the LBLOCA scenario well below the required maximum limit.