Assessment of ALWR passive safety system reliability. Phase 1: Methodology development and component failure quantification
- Sandia National Labs., Albuquerque, NM (United States)
- New Mexico Univ., Albuquerque, NM (United States)
Many advanced light water reactor (ALWR) concepts proposed for the next generation of nuclear power plants rely on passive systems to perform safety functions, rather than active systems as in current reactor designs. These passive systems depend to a great extent on physical processes such as natural circulation for their driving force, and not on active components, such as pumps. An NRC-sponsored study was begun at Sandia National Laboratories to develop and implement a methodology for evaluating ALWR passive system reliability in the context of probabilistic risk assessment (PRA). This report documents the first of three phases of this study, including methodology development, system-level qualitative analysis, and sequence-level component failure quantification. The methodology developed addresses both the component (e.g. valve) failure aspect of passive system failure, and uncertainties in system success criteria arising from uncertainties in the system`s underlying physical processes. Traditional PRA methods, such as fault and event tree modeling, are applied to the component failure aspect. Thermal-hydraulic calculations are incorporated into a formal expert judgment process to address uncertainties in selected natural processes and success criteria. The first phase of the program has emphasized the component failure element of passive system reliability, rather than the natural process uncertainties. Although cursory evaluation of the natural processes has been performed as part of Phase 1, detailed assessment of these processes will take place during Phases 2 and 3 of the program.
- Research Organization:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 48627
- Report Number(s):
- SAND-92-1231; ON: DE95010401; TRN: 95:011881
- Resource Relation:
- Other Information: PBD: Apr 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
An approach for assessing ALWR passive safety system reliability
Methodology for the Incorporation of Passive Component Aging Modeling into the RAVEN/ RELAP-7 Environment