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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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.
W. F. Miller, Jr., Wm. H. Reed
Nuclear Science and Engineering | Volume 62 | Number 3 | March 1977 | Pages 391-411
Technical Paper | doi.org/10.13182/NSE62-391
Articles are hosted by Taylor and Francis Online.
Using projection operators, we rederive x-y geometry discrete ordinates-to-spherical harmonics (SN → PN-1.) fictitious sources defined in the literature as ray-effect mitigating devices. We define a new x-y geometry fictitious source with certain properties that are superior to earlier sources. A detailed description of the S2 → P1 source, including a discussion of vacuum and reflective boundary conditions, is provided. We then derive fictitious sources in r-z geometry that give spherical harmonics and spherical-harmonics-like solutions. Finally, a simple algorithm is presented that allows a significant reduction in the iteration time needed to obtain ray-effect-free solutions. This algorithm effectively reduces the size of the fictitious source in energy groups where ray-effect distortions are not expected. The new sources and the algorithm for reduction of computation time make this approach viable for solving the ray-effect problem.