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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.”
H. Kamide, K. Hayashi, T. Isozaki, M. Nishimura
Nuclear Technology | Volume 133 | Number 1 | January 2001 | Pages 77-91
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT01-A3160
Articles are hosted by Taylor and Francis Online.
A proper assessment of core thermohydraulics under natural circulation conditions is important so that the full potential of the inherent, passive feature of a fast reactor can be used. When the heat exchangers of the decay heat removal system are operated in the upper plenum of a reactor vessel, cold sodium exiting the heat exchangers may penetrate into the gap regions between fuel subassemblies; this gap flow between the wrapper tubes of subassemblies is called interwrapper flow (IWF). During natural circulation decay heat removal, IWF will significantly modify the flow and temperature distributions in the subassemblies. Sodium experiments were carried out to investigate these phenomena, using a test section consisting of seven subassemblies housed and connected to an upper plenum. The cooling effect of IWF on the fuel subassemblies was evaluated and a new nondimensional parameter was deduced to characterize this effect. On the other hand, IWF reduced the natural circulation flow in the primary loop due to a temperature decrease in the upper part of the core. A balance between the cooling effect and the flow reduction effect is discussed. Three-dimensional analyses were performed to establish an estimation method for IWF. For the temperature decreases due to IWF at the hottest point in the subassemblies there was good agreement between experiments and predictions.