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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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.
William T. Sha, Alan E. Waltar
Nuclear Science and Engineering | Volume 44 | Number 2 | May 1971 | Pages 135-156
Technical Paper | doi.org/10.13182/NSE71-A19663
Articles are hosted by Taylor and Francis Online.
A two-dimensional (R - Z) integral model for characterizing fast reactor excursions from accident inception through core disassembly is presented. For predisassembly calculations, a Eulerian geometric model is used and multichannel heat-transfer computations are performed. Reactivity feedback due to Doppler broadening, coolant density change and voiding, and fuel movement are taken into account. A Lagrangian coordinate system is used in the disassembly phase, wherein the neutronics balance consists of Doppler broadening and material motion. A unique feature of the model is the ability to accommodate a pointwise Energy-Density-Dependent Equation-of-State according to the local sodium inventory that actually exists at the time of disassembly. By providing a consistent basis for establishing the effective reactivity ramp rate, Doppler coefficient, appropriate Equation-of-State, and temperature distribution at the start of core disassembly, much of the arbitrariness normally associated with large accident analyses can be removed. For most accident analyses, this model predicts a significantly lower energy yield during a superprompt critical nuclear excursion than would be computed by using the conventional modified Bethe-Tait analysis.