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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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Jul 2024
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Nuclear Science and Engineering
September 2024
Nuclear Technology
August 2024
Fusion Science and Technology
Latest News
Taking shape: Fusion energy ecosystems built with public-private partnerships
It’s possible to describe fusion in simple terms: heat and squeeze small atoms to get abundant clean energy. But there’s nothing simple about getting fusion ready for the grid.
Private developers, national lab and university researchers, suppliers, and end users working toward that goal are developing a range of complex technologies to reach fusion temperatures and pressures, confounded by science and technology gaps linked to plasma behavior; materials, diagnostics, and electronics for extreme environments; fuel cycle sustainability; and economics.
Po-Jung Chiu, Chung-Kung Lo, Tai-Hung Wu
Nuclear Technology | Volume 209 | Number 1 | January 2023 | Pages 53-68
Technical Paper | doi.org/10.1080/00295450.2022.2105633
Articles are hosted by Taylor and Francis Online.
We discuss the specific risk significance in the extended pre-defueled (PD) phase of the decommissioning process, particularly if spent fuels are still in the core due to the low-power and shutdown refueling plant operating state (POS). The issue of full-core discharge capability after permanent shutdown during the PD phase motivated this study on the evolution of system risks using a reference plant design of the two-unit/BWR-4/Mark-I.
The effects of the reactor core and the spent fuel pool (SFP) on the incorporative risks are explored. The probabilistic risk assessment methodology, including the technical elements, is systematically developed by defining two primary configurations from the internal event analysis under the models 30, 60, 180, 365, and 942 days after permanent shutdown, respectively. The movable refueling gate between the reactor core and the SFP, as well as the residual heat removal (RHR) system, have been subjected to two sensitivity studies on system configurations in order to examine the induced impacts by the refueling gate and cooling systems. MELCOR, a realistic thermal-hydraulic code, is utilized to determine the decay heat levels and the success criteria after shutdown. The two operator tasks are assumed to be independent in the situation of decreasing decay heat after shutdown and a long time available for human actions.
In addition, the WinNUPRA software package is used for the fuel uncovery sequence quantification. Plant-centered loss-of-offsite power (LOOP), flow diversion loss-of-coolant accidents (LOCAs) to the suppression pool via the RHR system, switchyard-centered LOOPs, and LOCAs in the connected systems via the RHR, have proven to be the most significant initiating events for the configurations. When compared to the low-power and shutdown refueling POS, the realistic quantification results in terms of fuel uncovery frequencies and the evolution of the risk profile for the basic and sensitivity configurations meet the expectations under the PD-phase condition of low-decay heat levels.