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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.”
Noritoshi Minami, Toshiaki Chikusa, Michio Murase
Nuclear Technology | Volume 164 | Number 2 | November 2008 | Pages 265-277
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT08-A4025
Articles are hosted by Taylor and Francis Online.
Different flow patterns of steam forward flow and nitrogen reverse flow in U-tubes were observed in the reflux condensation experiments using the Bethsy facility with 34 U-tubes. In this study, the behavior was calculated using RELAP5/MOD3.2 with two and three flow channels of U-tubes. By the modification of the weighting factor for the calculation of friction coefficients, the nitrogen reverse flow was successfully calculated. In the calculations changing the flow area ratio of two flow channels, the number of active U-tubes with steam forward flow was predicted using the assumption that flow was most stable in the case with the maximum nitrogen recirculation flow rate, and it agreed rather well with the observed number of active U-tubes (19 to 24 U-tubes) within the difference of 4 U-tubes. In the calculations with three flow channels, without the assumption, the average of the ratios of active U-tubes in several calculations (four cases in this study) with different flow area ratios of the three flow channels gave good prediction of the ratio of active U-tubes. The results indicate the validity of the assumption that the flow with the maximum nitrogen recirculation flow rate may be the most stable and appear most probably among different numbers of active U-tubes.
