Design Basis Accidents (DBA) and Beyond DBAs constitute a key step in the design and licensing process of any nuclear system. The analysis of DBA and BDBAs requires knowledge of the behaviour of the system under very dynamic sequences as well as detailed understanding of local phenomena. The members of ENSO have a long experience in the simulation of both system behavior and local phenomena. The expertise has been built through the participation to integral experimental programs as well as the simulation of separate effect tests. This step is essential in order to guarantee the validity of analyses for commercial nuclear systems.
The experience of the group in this area comprises:
- Participation to experimental programs at integral test facilities. ENSO members have developed or used models to simulate experiments at the following facilities: PKL (AREVA), LSTF (JAEA), ATLAS (KAERI), LOFT, BETHSY and LOBI.
- Simulation of DBA and BDBA scenarios for NPP full plant nodalizations. In these area, works have been done for the following power plants: Ascó 1&2 (PWR), Vandellós 2 (PWR), Laguna Verde (BWR), Ringhals (BWR), TMI (PWR), Zion (PWR).
- Best estimate plus uncertainty analysis.
- Revision of Emergency Operating Procedures.
Performing DBA and BDBA analysis requires full understanding of both system behaviour and local phenomena