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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.”
J. Devooght, H. B. Smets
Nuclear Science and Engineering | Volume 28 | Number 2 | May 1967 | Pages 226-236
Technical Paper | doi.org/10.13182/NSE67-A17472
Articles are hosted by Taylor and Francis Online.
Nonlinear stability criteria for reactors (Welton, Popov, etc.) can only be used when the reactor is linearly stable at all equilibrium power levels. This paper contains four methods of analysis of nonlinear stability that can be used when the reactors are unstable above a certain equilibrium power. The topological method and the second Liapunov method are often of no practical interest, while the Aizermann and Rosen methods are applicable irrespective of the complexity of the system. The different methods are compared in the case of a reactor with a prompt-positive temperature coefficient and a slow-negative temperature coefficient.
