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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.”
Kresna Atkhen, Georges Berthoud
Nuclear Technology | Volume 142 | Number 3 | June 2003 | Pages 270-282
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT03-A3389
Articles are hosted by Taylor and Francis Online.
Within the framework of severe reactor accident studies, we present experimental and numerical parametric studies on debris bed coolability. Data are provided by the SILFIDE multidimensional experimental facility at Electricité de France. The bed is composed of inductively heated steel sphere beads (diameters ranging from 2 to 7.18 mm) contained in a 50- × 60- × 10-cm vessel. Numerical computations are obtained with MC3D REPO developed by Commissariat à l'Energie Atomique.Because of heterogeneous power distribution within the bed, two definitions (mean and local) for the critical heat flux (CHF) are proposed. Even in the first case, the CHF was higher than the Lipinsky one-dimensional flux. As the power is being increased, temperature plateaus above saturation temperature are observed. An analysis is proposed, based on possible different hydrodynamic flow configurations occurring in postdryout regimes. In some experiments, some spheres were superficially molten and stacked together, but globally, the bed was still coolable.The influence of operational parameters such as bottom coolant injection, height of the water, fluidization of upper particles, and subcooled liquid injection on dryout phenomena and CHF values are also described.The MC3D-REPO calculations assuming a thermal equilibrium between the three phases gives results in accordance with experimental data.