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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 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.”
Marco Pellegrini, Hiroaki Suzuki, Hideo Mizouchi, Masanori Naitoh
Nuclear Technology | Volume 186 | Number 2 | May 2014 | Pages 241-254
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-107
Articles are hosted by Taylor and Francis Online.
Because of the high-magnitude earthquake and consequent tsunami that struck the east coast of Japan on March 11, 2011, at 14:46, Tokyo Electric Power Company's Fukushima Daiichi nuclear power plant experienced station blackout (SBO) resulting in a nuclear accident unprecedented in time and extent. Simulation of such an accident by means of computer codes is largely dependent on the applied boundary conditions and physical models. However, still-unknown boundary conditions and unclear phenomena result in uncertain computed quantities. In this study, first, the boundary conditions of emergency systems are theoretically derived, starting from a discussion of the reactor available measured quantities and related uncertainties. Then, newly implemented physical models (e.g., wetwell condensation mechanism), which were not accounted for in historical studies of long-term SBOs, are explained. As an early method for accident clarification and explanation regarding effective boundary conditions, results from the SAMPSON severe accident code were compared with theoretical values. The results of SAMPSON compared with the measured quantities available have shown that despite successful safety operations performed by the plant operators in Fukushima Daiichi Unit 3, the eventual lack of batteries (for systems operation and measurement reading) led to plant conditions of low core water level at high pressure, nullifying the attempt of the subsequent alternative water injection to prevent core degradation.