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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.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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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Nuclear moratoriums crumble around the world
The recent surge in positive sentiment about nuclear as the most viable answer to global energy needs and decarbonization goals has found governments around the world taking steps to reverse course on decades-old bans, moratoriums, and restrictions on new nuclear development.
Rae-Joon Park, Sang-Baik Kim, Hee-Dong Kim, Sang-Min Choi
Nuclear Technology | Volume 127 | Number 1 | July 1999 | Pages 66-80
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT99-A2984
Articles are hosted by Taylor and Francis Online.
An experimental study has been performed on natural convection heat transfer with and without crust formation in a molten metal pool. Two types of steady-state tests, natural and forced convection coolings of the molten metal pool, were performed in low- and high-aspect-ratio cases. When the natural convection flow is developed in the molten metal pool, the overlying coolant conditions do not affect the crust formation. On the other hand, when the natural convection flow is not developed, the coolant conditions affect the crust formation. The heat transfer rate of cases with crust formation is lower than that of cases without crust formation due to the effect of the crust serving as a thermal barrier. The present experimental results on the relationship between the Nusselt number and Rayleigh number match better with Globe and Dropkin's correlation than any others. With an increase in the crust thickness, the Nusselt number in the metal pool does not rapidly decrease in spite of a rapid decrease in Rayleigh number because the aspect ratio of the metal pool decreases. A new correlation between the Nusselt number and Rayleigh number in the molten metal pool with crust formation has been developed as Nu = 0.0923 (Ra)0.302 (2 × 104 < Ra < 2 × 107).