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Division Spotlight
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.
Meeting Spotlight
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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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 since 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. local time 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.”
Noritoshi Minami, Toshiaki Chikusa, Michio Murase
Nuclear Technology | Volume 164 | Number 2 | November 2008 | Pages 265-277
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT08-A4025
Articles are hosted by Taylor and Francis Online.
Different flow patterns of steam forward flow and nitrogen reverse flow in U-tubes were observed in the reflux condensation experiments using the Bethsy facility with 34 U-tubes. In this study, the behavior was calculated using RELAP5/MOD3.2 with two and three flow channels of U-tubes. By the modification of the weighting factor for the calculation of friction coefficients, the nitrogen reverse flow was successfully calculated. In the calculations changing the flow area ratio of two flow channels, the number of active U-tubes with steam forward flow was predicted using the assumption that flow was most stable in the case with the maximum nitrogen recirculation flow rate, and it agreed rather well with the observed number of active U-tubes (19 to 24 U-tubes) within the difference of 4 U-tubes. In the calculations with three flow channels, without the assumption, the average of the ratios of active U-tubes in several calculations (four cases in this study) with different flow area ratios of the three flow channels gave good prediction of the ratio of active U-tubes. The results indicate the validity of the assumption that the flow with the maximum nitrogen recirculation flow rate may be the most stable and appear most probably among different numbers of active U-tubes.