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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.”
Allen C. Smith, James E. Blake, Michael T. Childerson, Ted R. Ohrn, Robert M. Privette
Nuclear Technology | Volume 106 | Number 2 | May 1994 | Pages 254-260
Technical Note | Heat Transfer and Fluid Flow | doi.org/10.13182/NT94-A34980
Articles are hosted by Taylor and Francis Online.
Analytical studies of the effects of power on flow instability in parallel channels with upward flow of coolant have predicted that the Ledinegg flow instability, encountered as flow is decreased for typical operating power levels, would not be experienced at low-power levels. For a system in which the flow of coolant is upward, the increased buoyancy enhances flow in the channel, so that as the void increases, the overall pressure loss decreases. Under this condition, flow instability does not occur. Testing was performed to confirm the predicted behavior and to provide data for benchmarking of computer codes used for predicting the performance of reactor fuel elements. The demand curves traced in these tests are part of the multidimensional demand surface for the test apparatus. The basic coordinates of this surface are flow rate, pressure drop, and power. A fourth significant independent variable is system pressure, so that the behavior of the system is represented by a family of Δp-flow-power surfaces for each pressure level. This testing confirmed that, at low power levels comparable to decay heat removal power, the buoyancy effects may become dominant so that the demand curve for the fuel assembly turns downward and flow instability will not occur.