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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.”
Yudai Tasaki, Akifumi Yamaji (Waseda Univ)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 1144-1152
The concept of “multi-axial fuel shuffling” has been recently proposed for a high breeding core design of supercritical- water cooled reactor. In this study, the same design principle is applied to boiling water reactor (BWR) condition. The results show that the Compound System Doubling Time (CSDT) can be reduced by increasing fuel batch number of the upper blanket layer, but more investigations may be necessary to consider further improvement of the core breeding performance.
Moreover, fuel performance of the axially heterogeneous core has been evaluated with the power history obtained by the core calculations and modified FEMAXI-7 code which consider two different types of pellets (i.e., MOX and depleted uranium) within one fuel rod. The analysis results indicate that uncertainty in thermal conductivity of MOX pellets may be important in evaluating the peak pellet temperature, while relatively large plenum volume may be required at the bottom of the fuel rod to accommodate the large amount of fission gas release. Another potential design issue may be the cladding outer diameter increase by the MOX pellet swelling, which may have significant influence on evaluation of MCHFR.