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ANS Student Conference 2025
April 3–5, 2025
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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.”
Hyoung Kyu Cho, Yun Je Cho, Moon Oh Kim, Goon Cherl Park
Nuclear Technology | Volume 159 | Number 1 | July 2007 | Pages 39-58
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3855
Articles are hosted by Taylor and Francis Online.
In this study, a new concept in reactor cavity cooling systems (RCCSs) for high-temperature gas-cooled reactors (HTGRs) is proposed. The proposed RCCS consists of both water pools and active air-cooling systems, in order to overcome the disadvantages of the weak cooling capability of the air-cooled RCCS and the complex cavity structures of the water-cooled RCCS. The cooling capability of the RCCS during normal operation and under accident conditions was evaluated on the basis of a series of experiments that were performed in a scaled test facility. The reactor vessel of the test facility was a 1/10 linear scaled model of a 265-MW pebble bed modular reactor (PBMR), and the RCCS of the test facility was designed to limit the volumetric-averaged reactor vessel wall temperature below the maximum permissible wall temperature of the prototype reactor. The experiments were conducted by simulating the heat released from the reactor vessel wall to the RCCS. The power was reduced by 1/100 to preserve the heat flux, and the timescale was reduced by 1/10 to preserve the stored energy per volume. In the normal operation tests, detailed information on the temperature distribution and heat removal fraction of the upper pool and side pool was obtained. In the loss of all forced convection accident test, the passive afterheat removal capability of the RCCS was evaluated. These experimental results will be used to validate the reactor safety analysis codes and to evaluate the feasibility of the water pool-type RCCS.