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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.”
Byoung Jae Kim, Jungwoo Kim, Kyung Doo Kim
Nuclear Science and Engineering | Volume 178 | Number 2 | October 2014 | Pages 225-239
Technical Paper | doi.org/10.13182/NSE13-57
Articles are hosted by Taylor and Francis Online.
When fluid particles such as bubbles and droplets are not in contact with the wall, one probably neglects the wall drag term in the one-dimensional momentum equation for the dispersed phase. This treatment however leads to an unphysical prediction of the motion of the dispersed phase. In the framework of the conventional two-fluid model, how to apply the wall drag to the dispersed phase is disputable. The interface force acting on a fluid particle results from the interaction between the fluid particle and the surrounding continuous fluid. To clarify the contributions to the forces acting on the dispersed phase, the volume-averaged momentum equations are formulated based on the equation of a single fluid particle motion. After that, one-dimensional momentum equations are newly obtained from the averaged equations. It is shown that the wall drag term in the dispersed phase is associated with the spatial gradient of the volume-averaged viscous stress of the continuous phase. The magnitude of the wall drag term for a phase is its volume fraction multiplied by the total two-phase pressure drop induced by the wall shear of the continuous phase.