Views on R&D needs about in-vessel reflooding issues, with a focus on debris coolability
Titre de la revue : Nuclear Engineering and Design
Volume : 236
N° : 19-21
Pagination : 1976-1990
Date de publication : 01/10/2006
In-vessel reflooding during a severe accident in a PWR was analyzed in 2000-2002 by a group of experts with the aim to prepare a global IRSN R&D strategy to answer the corresponding pending safety issues. Indeed, water is today systematically injected if available during a severe accident in a PWR. However, knowledge on consequences of such an injection is not complete and answers are necessary for accident management in present PWR as well for design and safety analysis of future PWR: is in-vessel corium retention possible? What is the kinetics of hydrogen production? What is the reactor cooling system (RCS) re-pressurization? Is there a risk of steam explosion (steam explosion is not discussed in this paper)? What is the impact on source term? And more generally, how to optimize water injection? (When? How?) R&D needs of investigation of these aspects were identified. This should cover separate-effect and integral tests, as well as modeling and code development.