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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Fusion Science and Technology
Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Kenji Kotoh, Masashi Kawahara, Keisuke Kimura, Kazuhiko Kudo
Fusion Science and Technology | Volume 56 | Number 1 | July 2009 | Pages 179-183
Tritium, Safety, and Environment | Eighteenth Topical Meeting on the Technology of Fusion Energy (Part 1) | doi.org/10.13182/FST09-A8898
Articles are hosted by Taylor and Francis Online.
Cryogenic pumps are convenient machinery for handling hydrogen isotopes in fusion fuel processing systems. Not only ultra-vacuum pumps working at such as liquid helium or hydrogen temperature but also sorption pumps using liquid nitrogen are applicable. The latter type is suitable to a means of temporary storage and/or transportation between process units. In the cryogenic pumping, there is an issue that the pressure in a pump is not necessarily identical with the pressure measured in its evacuating vessel in equilibrium, because of an effect of thermal transpiration. Thermal transpiration is important in adsorption isotherms which characterize cryo-sorption pumping. In this study, the effect of thermal transpiration was investigated for He, H2 and D2 in a closed system consisting of a volume at room temperature and a volume at cryogenic temperature, connected together by a simple narrow pipe or a pipe containing baffle plates as thermal shield. The effect is here described by an equation of nominal-distribution function with respect to the pressure measured in the hot end volume. Defining an effective inner diameter for the latter pipe, agreement is shown of characteristic curves for geometrically different pipes. The error-functional curves for H2 and D2 are agreed together. The curve for He is also perfectly approximated but with a constant shift. This shift results in the difference of a molecular property among He, H2 and D2.