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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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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
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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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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.
Wadim Jaeger, Wolfgang Hering (KIT)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 846-859
In this paper, a review of experiments related to liquid metal heat transfer under mixed convection is performed. This study is relevant because heat transfer during start-up and shut-down procedures, and operational transients is influenced by natural convection, resulting in mixed convection, which differs considerably from forced convection. Up to now, simulation tools like TRACE, RELAP, etc. apply only forced convection models for liquid metal heat transfer. The influence of mixed convection on the heat transfer during the above mentioned transients is completely ignored. Hence, it is not possible to simulate mixed convection with best-estimate system codes like TRACE or RELAP. In order to perform realistic simulations of plants and experimental facilities mixed convection must be addressed and considered. Therefore, the literature is reviewed for experimental data with liquid metal heat transfer under mixed convection and generally applicable statements and models will be provided. A clear distinction in the heat transfer behavior for low and high Péclet number flows can be identified. Thereby, a Péclet number dependency is visible for higher Péclet numbers (Pe > 100). Furthermore, the heat transfer (Nusselt number) cannot be presented as a function of one dimensionless parameter. To identify underlying phenomena, especially when comparing different experimental scenarios several dimensionless numbers are needed (Gr*, B, Z, etc.). Based on this study, it is possible to derive a model for the heat transfer under mixed convection. Nevertheless, these findings and the sparse number of experiments also indicate the need for new and comprehensive experiments.