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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.”
Luciano Burgazzi
Nuclear Technology | Volume 156 | Number 2 | November 2006 | Pages 150-158
Technical Paper | Reactor Safety | doi.org/10.13182/NT06-A3781
Articles are hosted by Taylor and Francis Online.
The inclusion of passive safety-related systems within the advanced reactor design claims high system availability and reliability. A detailed system and safety analysis applying the failure mode and effect analysis (FMEA) approach is required as a primary step for the development of a methodology aimed at the reliability assessment of passive systems. The present study concerns thermal-hydraulic passive systems that are designed for decay heat removal and rely on natural circulation that foresee a heat exchanger immersed in a cooling pool. The main purposes of the work are to identify important accident initiators, find out the possible consequences to the plant deriving from component malfunctions, individuate possible causes, identify mitigating features and systems, and classify accident initiators in initiating events of accident sequences. A qualitative overview of accident sequences could be derived from the FMEA tables looking at consequences' description and preventive and corrective actions. Failure probabilistic evaluations are included as well to point out the probabilities and frequencies to have the plant in fault and/or unavailability conditions during passive system operation, therefore ensuring a complete set of initiating events of reactor accident sequences. Finally, important feedback to the design activities will derive from the FMEA study performed for safety assessment purposes. An important lesson elicited from the analysis is that measures against common-cause failures can reduce significantly the probability of failure of the system.