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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.”
Tatjana Jevremovic, Yoshiaki Oka, Sei-Ichi Koshizuka
Nuclear Technology | Volume 114 | Number 3 | June 1996 | Pages 273-284
Technical Paper | Fission Reactor | doi.org/10.13182/NT96-A35232
Articles are hosted by Taylor and Francis Online.
The core design of a fast converter reactor adopting enriched UO2 fuel is studied for maximizing the power rating of the direct-cycle, supercritical water-cooled fast reactor with the same reactor pressure vessel as the breeder and mixed-oxide (MOX) fueled converter. The coolant void reactivity is kept negative by placing thin zirconium-hydride layers in the blanket fuel assemblies facing the driver fuels, as in our fast breeder reactor design. Compared with the fast converter adopting MOX fuel, the electric power output is increased 11%, from 1444 to 1625 MW(electric). It is attained by the reduced blanket fuel fraction for keeping negative reactivity at coolant voiding. The positive reactivity at flooding the core is much larger than that of the MOX core, but it can be managed by the control rod system. The conversion ratio, the surviving ratio, is 0.85, reduced 0.1 from that of the MOX converter. The enrichment of UO2fuel reaches 16.9%. The specific fissile inventory is the highest, compared with the MOX-fueled converter and breeder due to the lower fission cross sections of 235U. The cores of the supercritical water-cooled reactors are radially heterogeneous. The decoupling problem is, however, much smaller than that of the liquid-metal fast breeder reactor due to the smaller core diameter. The hydrogen loss from the zirconium hydrides at steady state and accidental conditions does not impose a problem.