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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. V. Muralidhar Rao, S. M. Lee
Nuclear Science and Engineering | Volume 82 | Number 1 | September 1982 | Pages 71-77
Technical Paper | doi.org/10.13182/NSE82-A19029
Articles are hosted by Taylor and Francis Online.
The homogenized neutron diffusion equation for Benoist’s uncorrected diffusion coefficients is derived. The approximations in the asymptotic and buckling methods are analyzed to show that both these methods are identical and that Benoist’s corrected diffusion coefficients should not be used in the diffusion equation. Furthermore, the practical limitations of the homogenization methods are discussed, and it is pointed out that the use of Benoist’s uncorrected coefficients in the diffusion equation may be superior to the use of the coefficients of Larsen or of Deniz and Gelbard. It is also recommended, in view of the severe approximations made in the transport theory to arrive at the homogenization prescriptions, that the accuracy in the results of the homogenization methods should be examined for a few benchmarks in slab geometry which are amenable to transport theory solution.
