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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.”
G. A. Krist, C. G. Poncelet
Nuclear Science and Engineering | Volume 51 | Number 4 | August 1973 | Pages 347-375
Technical Paper | doi.org/10.13182/NSE73-A23272
Articles are hosted by Taylor and Francis Online.
An investigation of the stability of a nuclear power reactor subject to random macroscopic parameter variations is performed. An analysis procedure for determining the effect of stochastic coefficients on the stability in the mean and mean square of linear systems is presented. The procedure is based on Gaussian white process variations which can be shown to be governed by the Fokker-Planck equation. Moment equations are extracted from the Fokker-Planck equation and serve as system equations used for the stability analysis. It is shown that for some simple space-independent reactor models it is possible for random macroscopic parameter variation to destabilize in the mean and mean square a deterministically stable system. Conversely, the study has shown that under certain conditions random macroscopic variation of system parameters can also stabilize in the mean and mean square, a system which is deterministically unstable. A coupled-core spatial reactor model is utilized for the investigation of xenon instability. The results of this analysis again indicate that random macroscopic parameter variation can be a stabilizing or destabilizing influence. Analog simulations of linear systems with stochastic coefficients and a simple reactor model are used to verify the analysis procedure developed in this research.