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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.”
Mohamed Belhadj, Tunc Aldemir, Richard N. Christensen
Nuclear Technology | Volume 82 | Number 3 | September 1988 | Pages 330-340
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34134
Articles are hosted by Taylor and Francis Online.
Currently used correlations to predict the onset of nucleate boiling heat flux in research reactor channels determine in terms of local channel pressure and wall superheat. Recent experiments show that these correlations may over- or underestimate by as much as a factor of 5 in thin rectangular channels for low-velocity upward flows. Such flow conditions are encountered in the natural convection cooling of research reactors with plate-type fuels. A set of experiments are performed to quantify the effect of channel flow velocity and gap size (in the ranges of 2 to 14 cm/s and 2 to 4 mm, respectively) on for upward flow in rectangular channels. An adjustable gap between two internally heated aluminum blocks forms the flow channel. Other controlled variables are channel mass flow rate, heat generation rate in the aluminum blocks, and coolant temperature at the channel inlet. The shape of the power distribution along the channel walls (truncated cosine), channel height (642 mm), width (73 mm), and surface roughness simulate operating conditions in research reactors using plate-type fuels. The experimental results show that (a) both channel gap size and flow velocity are important parameters in determining under low-velocity, upward flow conditions and (b) currently used correlations yield the upper and lower bounds on under these conditions. A new correlation is proposed that predicts the experimental results within 13% for flows with Re <700 (Re based on channel gap) and that is valid in the 1.40- to 1.46-atm pressure range.