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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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.”
Sai K. Mylavarapu, Xiaodong Sun, Richard N. Christensen
Nuclear Science and Engineering | Volume 182 | Number 3 | March 2016 | Pages 319-331
Technical Paper | doi.org/10.13182/NSE14-107
Articles are hosted by Taylor and Francis Online.
Hydrodynamically developing and fully developed laminar flows in a semicircular duct are numerically and analytically investigated, respectively. As part of the analytical approach, scale analysis is used to develop order-of-magnitude estimates for the friction factor–Reynolds number product for developing and fully developed laminar flows in a semicircular duct. Dimensionless axial velocity distribution is determined and presented in terms of the dimensionless pressure drop constant for hydrodynamically fully developed laminar flow. Fully developed laminar frictional characteristics for flow through a semicircular duct are then deduced from the dimensionless axial velocity distribution, from which the location of maximum axial velocity and the ratio of maximum axial velocity to the mean axial velocity are determined. In addition, hydrodynamically developing laminar flow in a semicircular duct is numerically analyzed. Various developing flow region parameters, such as the apparent Fanning friction factor and incremental pressure drop number, for laminar flows in a semicircular duct are determined from the numerical analysis. Furthermore, the fully developed laminar flow results obtained from the numerical analysis are compared with the analytical solution, and good agreement is observed between them.
