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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.”
Scott D. Ramsey, Roy A. Axford, Gregory J. Hutchens
Nuclear Science and Engineering | Volume 166 | Number 1 | September 2010 | Pages 73-81
Technical Note | doi.org/10.13182/NSE09-63TN
Articles are hosted by Taylor and Francis Online.
Stochastic point kinetics neglecting delayed neutrons has been subject to rigorous analysis in the years since its introduction. Many approximate solutions appearing within this context are based upon the “quadratic approximation,” where fission multiplicity is truncated at two. In this technical note we review the quadratic approximation within the context of a stochastic, space-independent, one-energy-group model neglecting delayed neutrons and its generalization to higher-order approximations in transient and stationary systems. This generalization results in the probability of a zero neutron population for a source-free system being governed by transcendental and polynomial algebraic equations in the transient and infinite time limit cases, respectively. For 239Pu, we solve the transcendental equation over a wider range of prompt multiplication factors and times than has been previously accomplished. We also reproduce and generalize associated solutions of the polynomial algebraic equation. In both cases, solutions are computed for successive generalizations of the quadratic approximation to higher-order maximum fission multiplicity.
