Ability of Current Advanced Codes to Predict Core Degradation, Melt Progression and Reflooding: Benchmark Exercise on an Alternative TMI-2 Accident Scenario


This Phase II exercise was the first benchmarking of severe accident codes promoted by NEA in almost 20 years. The objective of the exercise was to perform a code benchmark on a well-defined plant (similar to TMI-2) and with prescribed boundary conditions. Therefore, the benchmark avoided additional and unwanted sources of discrepancies between code calculations, so as to focus on the variability of the codes calculations of core degradation. This report includes all the information concerning the preparation of the benchmark, the results, and the conclusions of the exercise.