EPRI FUKSUHIMA TECHNICAL EVALUATION PROJECT MAAP5 FUKUSHIMA DAI-ICHI ACCIDENT SIMULATIONS

摘要

The Electric Power Research Institute (EPRI) has initiated a project to evaluate the severe accident progression at Fukushima Dai-ichi. The key goals of this project are to 1) establish the detailed understanding of the accident progression, in particular the types of challenges to the fission product barriers, 2) establish a repository of qualified critical event data, 3) identify areas where severe accident modeling could be enhanced, and 4) develop insights to improve plant safety through accident management measures. This paper reports the initial MAAP5 modeling of the Fukushima Dai-ichi Unit 1, Unit 2 and Unit 3 accident progressions. Based on the currently available information of the state of the units during and after the event, these severe accident simulations assess the likely fission product barrier failure modes together with the key sensitivities influencing accident progression. The focus of these simulations is to develop a model of severe accident progression which can represent the available measurements from each of the units to gain further insights regarding the types of challenges to various fission product barriers which might have occurred during the respective accident progressions.