DOI: 10.1615/ICHMT.1995.RadTransfProcHeatMassTransfSevNuclReactAcc
ISBN Print: 978-1-56700-059-7
U.S. NRC SEVERE ACCIDENT CODES - PROGRESS, STATUS AND FUTURE DIRECTION OF MODELING AND SUPPORTING EXPERIMENTAL ACTIVITIES
ABSTRACT
The U.S. NRC has invested considerable resources over the past 15 years to develop a qualitative and quantitative understanding of severe accident phenomena and related issues for light water reactors (LWRs). This understanding has resulted in the development of analytical models and integrated computer codes (e.g., SCOAP/RELAP5, CONTAIN, MELCOR) and data sufficient to support plant risk assessments, resolve certain severe accident issues for operating and future plants, and identify areas requiring further research and modeling improvement. This paper focuses on what has been accomplished and what remains to be done to further enhance our understanding and ability to predict certain severe accident phenomena. It addresses severe accident related phenomena from the perspective of how well they can be modelled and predicted and what are the remaining uncertainties. Future experimental and modeling work that can reduce the uncertainties and yield further improvements to models in severe accident codes are discussed.