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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.”
Michael L. Corradini, Warren M. Rohsenow, Neil E. Todreas
Nuclear Science and Engineering | Volume 73 | Number 3 | March 1980 | Pages 242-258
Technical Paper | doi.org/10.13182/NSE80-A19849
Articles are hosted by Taylor and Francis Online.
A major portion of the safety analysis effort for the liquid-metal fast breeder reactor is involved in assessing the consequences of a hypothetical core disruptive accident. A postulated loss-of-flow transient without scram may produce a two-phase fuel source at high pressures. The heat transfer process between the fuel and the sodium coolant as it is ejected into the upper plenum is described in this study. One mechanism that can cause the coolant to become entrained in the two-phase fuel is Taylor instabilities. The characteristic size of the entrained coolant droplets is considered to be equal to the critical wavelength of a Taylor instability. Analysis of full-scale reactor conditions indicates that the dominant heat transfer mechanism is radiation. Also, if noncondensible gases are absent, fuel vapor condensation on the sodium coolant droplets is controlled by mass diffusion, hence the subsequent rate of coolant vaporization is small. The net effect of the heat transfer is to reduce the fuel vapor pressure and reduce the expansion work by a factor of 1.2 to 2.5. Small-scale simulant experiments utilizing refrigerants could confirm the fuel condensation/sodium vaporization behavior, while reactor material tests must be done to investigate the radiation heat transfer mechanism.