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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.”
Yousef M. Farawila, Douglas W. Pruitt
Nuclear Science and Engineering | Volume 154 | Number 3 | November 2006 | Pages 302-315
Technical Paper | doi.org/10.13182/NSE06-A2635
Articles are hosted by Taylor and Francis Online.
A study of the nonlinear behavior of growing density-wave oscillations is presented in the framework of a reduced-order model. Nonlinear effects are included in both the hydraulic and neutron kinetics equations, where both were found to contribute to the observed limit cycles. In this paper, Part I, the basic concepts were developed and applied to the global oscillation mode, where only the fundamental neutron flux mode excitation is considered. Approximate analytical solutions for the limit cycle amplitude and the time evolution of the transient were derived. In Part II, the model order is increased to allow the representation of the azimuthal neutron flux harmonic and the simulation of growing regional mode oscillations. Analysis demonstrates that the regional mode, unlike the global mode, may not always reach a stable limit cycle, and if it does, the regional limit cycle amplitudes are large compared with the global mode. An extended reduced-order model has been developed for use as an accurate quantitative tool for simulating actual reactor situations, whereas the current paradigm restricts the applicability of reduced-order models to gaining qualitative insights.