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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.”
Ronald J. Lipinski, John E. Gronager, Michel Schwarz
Nuclear Technology | Volume 58 | Number 3 | September 1982 | Pages 369-378
Technical Paper | Fission Reactor | doi.org/10.13182/NT82-A32972
Articles are hosted by Taylor and Francis Online.
Received November 3, 1981 Accepted for Publication Feburary 24, 1982 The results of a fission-heated sodium-U02 particle bed heat removal experiment (D-4) are presented and the effects of cooling the overlying sodium below saturation are discussed. Single-phase convection began at a Rayleigh number an order of magnitude smaller than for water. Bed disturbances were observed to occur at the onset of boiling, but only after a previous boiling cycle. The disturbances are believed to be due to the flashing of superheated liquid sodium after noncondensable gases had been removed during a previous boiling cycle. The start of bed dryout was observed with two different overlying sodium temperatures (300 and 600°C). The dryout power was 0.77 kW/kg with 300°C overlying sodium (and 29 kPa pressure) and 3.58 kW/kg with 600°C sodium (and 43 kPa). It is believed that cold overlying sodium reduces the large heat-removal capability of shallow beds by causing vapor condensation within the bed and suppressing channel formation. Steady-state temperatures above the boiling temperature were observed at the bed bottom for several power levels above the incipient dryout power, indicating stable dry zones.