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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.”
Jiaxuan Tang, Daogang Lu, Jiangtao Liang, Xiangfeng Ma, Yizhe Liu, Shangshang Ye, Zihan Xia, Yuhao Zhang
Nuclear Science and Engineering | Volume 195 | Number 5 | May 2021 | Pages 478-495
Technical Paper | doi.org/10.1080/00295639.2020.1834314
Articles are hosted by Taylor and Francis Online.
The complex structure of a pool-type sodium-cooled fast reactor may lead to uncertainty and asymmetry of flow and temperature field distributions under a pump stuck accident. This phenomenon has obvious three-dimensional (3-D) thermal-hydraulic characteristics and cannot be analyzed by one-dimensional or two-dimensional models. Previous research has been limited and lacking of 3-D numerical data. Therefore, the commercial computational fluid dynamics software FLUENT is used to simulate a full-scale 3-D integrated model of the China Experimental Fast Reactor (CEFR) in order to obtain 3-D thermal-hydraulic characteristics of key structures and components in the pool-type sodium-cooled fast reactor under a pump stuck accident in the primary loop. The results show that a special asymmetrical backflow phenomenon may occur in the pressure tube and the intermediate heat exchangers (IHXs) of the failure loop under the accident, further leading to complicated flow and thermal characteristics in both the hot and the cold pools. There is obvious thermal stratification and asymmetric temperature distribution, within a temperature difference of more than 90°C between the different loops’ IHX outlet. The temperature difference between the upper and lower areas of the baffles is 20°C to 105°C. This research provides a detailed reference for engineering design and operation.