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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Yasunori Bessho, Takafumi Anegawa, Osamu Yokomizo, Yuichiro Yoshimoto, Masao Chaki, Motoo Aoyama, Takanori Fukahori
Nuclear Technology | Volume 127 | Number 1 | July 1999 | Pages 49-65
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT99-A2983
Articles are hosted by Taylor and Francis Online.
In the stability licensing analysis and evaluation of boiling water reactors (BWRs), frequency-domain stability analysis programs have been used in Japan. To back up the licensing analysis and evaluation, time-domain, multiregional analysis programs have been used because more detailed analytical results can be obtained by these programs with little more computer time than that used by the frequency-domain stability analysis programs. In the backup calculation by time-domain, multiregional analysis programs, many trial-and-error experiments and much expertise on the reactor core radial regional division and on the initial disturbance input are necessary to analyze properly the stability of the BWR core, particularly its regional nuclear thermal-hydraulic stability.A three-dimensional time-domain core dynamics analysis program called SUPER-STANDY was developed with a detailed mesh division that makes various trial-and-error procedures and experience-based expertise unnecessary and that can treat the stability peculiar to the BWR core accurately. The program was applied to a plant where regional instability was observed, and the results were qualified. They showed that BWR stability can be analyzed using SUPER-STANDY by adding only the core uniform initial disturbance input without considering the reactor core radial regional division.It was determined that core regional mode instability can be properly analyzed by the multiregional analysis program (a) by dividing the core into six or more radial regions, (b) by specifying the hot fuel bundle as one region, and (c) by specifying the surrounding fuel bundles around the hot fuel bundle as one region.A visual display system was also developed for a huge number of stability data and core nuclear thermal-hydraulic characteristics, which are connected to each other in a complex way. These are obtained by the SUPER-STANDY program.