1.2 Present Status of Continment Integrity Tests at NUPEC

摘要

Objectives of Containment Integrity Tests (CIT) conducted at NUPEC are to demonstrate reactor containment vessel integrity during severe accident and to respond to Phase II accident management (AM) concerns regarding uncertainty of phenomena, raised by Japan Atomic Energy Safety Commission. CIT consists of experiments and analysis of debris cooling phenomena, hydrogen combustion behavior, fission products transport behavior and containment structural behavior. The uncertain phenomena regarding Phase II AM(defined as AM after reactor pressure vessel failure) treated at NUPEC are fuel-coolant interaction (FCI) and molten core-concrete interaction phenomena during ex-vessel debris cooling, evaluation of peak pressure during hydrogen combustion, ultimate strength and leakage conditions in the containment vessel and effectiveness of fission products (FP) removal under Phase II AM conditions. Most of these studies have been conducted under the international cooperation including the participation of OECD project.