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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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2024 ANS Annual Conference
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Las Vegas, NV|Mandalay Bay Resort and Casino
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Lightbridge announces first U-Zr fuel rod samples extruded at INL
Lightbridge Corporation announced today that it has reached “a critical milestone” in the development of its extruded solid fuel technology. Coupon samples using an alloy of zirconium and depleted uranium—not the high-assay low-enriched uranium (HALEU) that Lightbridge plans to use to manufacture its fuel for the commercial market—were extruded at Idaho National Laboratory’s Materials and Fuels Complex.
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.