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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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Min Ho Lee (UNIST), Dong-Wook Jerng (Chung-Ang Univ), In Cheol Bang (UNIST)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 20-25
Reactor vessel auxiliary cooling system (RVACS) has been developed to make diverse safety system for sodium-cooled fast reactor (SFR). In the loss of flow (LOF) accident condition, decay heat from the core is transferred to the reactor vessel by natural circulation inside of the sodium pool. The reactor vessel transfers its heat to the containment vessel by the conduction and radiation through the gap between the reactor vessel and the containment. Finally, the containment vessel releases its heat to the air flow from the atmosphere, which is the ultimate heat sink, by means of the RVACS. Although natural circulation of sodium is an important phenomenon because it determines the sodium boiling, it has not been sufficiently researched for the case of the RVACS. Therefore, in this study, natural circulation of the sodium in the LOF condition was analyzed experimentally to evaluate the maximum sodium temperature in the LOF. Water was used as a simulant for the sodium with the reduced scale. The experimental apparatus was scaled down about 1/25 by length, focusing on the modified Boussinesq number which represents the ratio of heat transfer by the natural circulation to the conduction. Because the modified Boussinesq number was the same with that of the actual reactor, overall temperature distribution in scale-downed apparatus with water would be similar to that of the sodium pool. Difference between the maximum and the minimum temperature of the water pool in the experiment was about 0.7oC, which corresponds to 5.1oC temperature difference of the sodium in LOF condition of an actual reactor with the operation of the RVACS. By comparing temperature difference