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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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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.”
Rohan Biwalkar, Kenneth Redus, Adam Stein, Sola Talabi
Nuclear Science and Engineering | Volume 197 | Number 8 | August 2023 | Pages 2099-2116
Technical papers from: PHYSOR 2022 | doi.org/10.1080/00295639.2023.2204174
Articles are hosted by Taylor and Francis Online.
The current study describes a simulation-based analysis of the atmospheric dispersion of radionuclide fission product particles in the near-field and far-field of a generic, conceptual microreactor, which is a small nuclear reactor with a power output typically ranging from 1 to 20 MW(thermal) and generally lower than 50 MW(electric). The near-field is a distance of up to 100 m from the microreactor while the far-field is a distance of 300 m or beyond from the microreactor. The generic microreactor operates at a pressure close to the ambient pressure. Therefore, in the event of a postulated accident that causes the leakage of radionuclide particles from the microreactor containment into the environment, the radionuclide particles are unlikely to travel too far from the reactor, as opposed to conventional nuclear reactors. The current paper provides estimates of average and 95th-percentile values of the normalized effluent concentration of the atmospheric radionuclide particle dispersion with respect to the source strength in the near-field and far-field of the conceptual microreactor. The computer code Atmospheric Relative CONcentrations in Building Wakes (ARCON96) was used to perform all simulations for the current study. It was observed that the 95th-percentile values of the normalized effluent concentration decrease by an order of magnitude as the receptor distance increases, i.e., from the near-field to the far-field. The dispersed aerosol concentration also decreases with time. A parametric study was performed to understand which input parameters affect the normalized effluent concentration values the most, and a definitive screening design was employed for this purpose. The atmospheric stability class and the distance between the reactor and the receptor were the parameters found to affect the aerosol dispersion characteristics by the greatest extent. The study recommends that the computer code RADTRAD (Radionuclide Transport and Removal And Dose Estimation) be used to estimate the actual dosage over distance using the outputs from ARCON96 as inputs, along with reactor-specific core inventories.
