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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Amod Kishore Mallick, Anurag Gupta, Umasankari Kannan
Nuclear Science and Engineering | Volume 196 | Number 8 | August 2022 | Pages 927-942
Technical Paper | doi.org/10.1080/00295639.2022.2043541
Articles are hosted by Taylor and Francis Online.
Monte Carlo neutron transport codes have traditionally used a fixed-source scheme to simulate a subcritical system with an external source. The efficiency of this scheme is known to depend on the subcriticality level: The lower the subcriticality is, the worse is the efficiency. We have investigated an alternate iterative scheme, namely, the Monte Carlo iterative k-source (IKS) scheme, for the study of neutron subcritical multiplication. Our results show that the iterative scheme not only is as accurate, effective, and computationally efficient as the fixed-source scheme but also has the additional advantage of being weakly dependent on the subcriticality level. Also, the efficiency of this scheme is unaffected by the change in the location of the external source, unlike the fixed-source scheme where the efficiency decreases as the source is moved away from the fissile core center. The algorithm of this scheme is very similar to the algorithm of the eigenmode iterative scheme and hence can be easily implemented in the existing Monte Carlo codes. Our work establishes the validity and accuracy of the Monte Carlo IKS scheme, and with its incorporation in the production-level codes, it can be used for the physics design and analysis of accelerator-driven subcritical systems.
