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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Stephen M. Bajorek, Nikolay Petkov, Katsuhiro Ohkawa, Robert M. Kemper, Arthur P. Ginsberg
Nuclear Technology | Volume 136 | Number 1 | October 2001 | Pages 50-62
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT01-A3228
Articles are hosted by Taylor and Francis Online.
Since the 1988 Appendix K Rulemaking change, there has been significant interest in the development of codes and methodologies for "best-estimate" analysis of loss-of-coolant accidents (LOCAs). Most development has been directed toward large-break (LB) LOCAs (LBLOCAs), since for most pressurized water reactors (PWRs), the LBLOCA generates the limiting peak cladding temperature (PCT). As plants age, are uprated, and continue to seek improved operating efficiencies, the small break (SB) LOCA (SBLOCA) and intermediate-break (IB) LOCA (IBLOCA) can become a concern.Modifications have been made to the WCOBRA/TRAC-MOD7A code to enable it to make realistic calculations of SBLOCAs and IBLOCAs in a Westinghouse PWR. The MOD7A version has recently been approved for use as part of the Westinghouse best-estimate LOCA methodology for LBLOCAs. Thus, the modifications and improvements potentially allow LOCA calculations ranging from SBLOCAs to LBLOCAs using a single code version.The WCOBRA/TRAC-MOD7A, Rev. 4 SB02 version was used to calculate the transient response of a four-loop PWR for a range of break sizes located at the bottom of one of the cold legs. The break sizes ranged from a 0.051-m (2-in.) to a 0.406-m (16-in.) equivalent hole diameter. Each calculation was performed assuming American Nuclear Society (ANS) 1979 decay heat. The plant input assumed the loss of one train of safety injection as well as a power shape that was highly top skewed, which imposed some conservatism on the calculations but allowed a meaningful comparison to Appendix K-type analysis results. The realistic SBLOCA and IBLOCA results showed significantly reduced PCTs compared to those typically obtained from Appendix K LOCA calculations. The realistic results also can be categorized into four separate types of breaks, from a conventional slowly draining SBLOCA to an LBLOCA.