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Title: Historical perspectives of BEPU research in US

Journal Article · · Nuclear Engineering and Design
 [1];  [2]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. US Nuclear Regulatory Commission (NRC), Rockville, MD (United States)

Civilian nuclear energy started in earnest in the 1950s and experienced rapid growth in 1960-80s with increasingly larger reactors. These reactors were initially regulated based on the experience from the smaller reactors, but this could not be applied to the larger power reactors. Therefore, in 1974 the US Nuclear Regulatory Commission set up safety requirements based on defense in depth in 10 CFR 50.46, and set of guidance in 10 CFR 50 presented in Appendix K, for models and simulations of reactor safety analyses, to ensure conservatism in predicted safety parameters. These methods resulted in both conservative safety margins as well as economic and operational penalties. In the late 1970s and early 1980s, a large number of experiential programs provided data that allowed for the creation of best estimate models. These best estimate models showed the conservatism in Appendix K models. In 1988-89, USNRC modified the regulations and allowed the use of best estimate models provided they were coupled to a reliable and defensible measure of uncertainty in the prediction of safety parameters. This change in regulation strongly encouraged global activity for the development of best estimate codes and methods. To aide in this development, the USNRC provided one acceptable approach, the Code Scaling, Acceptability and Uncertainty Evaluation Methodology (CSAU). This approach was later refined in the Evaluation Model Development and Assessment Process (EMDAP).

Research Organization:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA), Office of Nonproliferation and Verification Research and Development (NA-22)
Grant/Contract Number:
SC0012704
OSTI ID:
1601334
Report Number(s):
BNL-213628-2020-JAAM; TRN: US2103626
Journal Information:
Nuclear Engineering and Design, Vol. 358, Issue C; ISSN 0029-5493
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 9 works
Citation information provided by
Web of Science

References (10)

Best estimate plus uncertainty analysis of departure from nucleate boiling limiting case with CASL core simulator VERA-CS in response to PWR main steam line break event journal December 2016
Overview of the NURESAFE European Project journal September 2017
Statistical aspects of best estimate method—I journal June 2003
Illustration of Sampling-Based Methods for Uncertainty and Sensitivity Analysis journal June 2002
Application of PWR LOCA margin with the revised Appendix K rule journal January 1992
Determination of Appendix K Conservatisms for Westinghouse Pressurized Water Reactors Using TRAC-PD2/MOD1 journal January 1987
Determination of Sample Sizes for Setting Tolerance Limits journal March 1941
The role of the PIRT process in experiments, code development and code applications associated with reactor safety analysis journal November 1998
Application of Fractional Scaling Analysis to Loss of Coolant Accidents, System Level Scaling for System Depressurization journal July 2009
An integrated structure and scaling methodology for severe accident technical issue resolution: Development of methodology journal November 1998