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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.”
John C. Lee, Thomas H. Pigford
Nuclear Science and Engineering | Volume 48 | Number 1 | May 1972 | Pages 28-44
Technical Paper | doi.org/10.13182/NSE72-A22454
Articles are hosted by Taylor and Francis Online.
Theoretical analysis of the explosive disassembly of fast reactors, following accidental loss of coolant and melting and gravity compaction of the fuel material,has been undertaken. A general expression for the rate of reactivity feedback dueto material disassembly in a core with more than one enrichment zone has been derived. Energy release in cylindrical geometry has been calculated with the effects due to zonal interfaces properly considered in the limit of zero acoustic speeds. The effect on the energy release of the assumption of fixed fuel density in the fuel equation-of-state has been investigated for oxide-fueled zoned cores. Fuel zoning can result in either greater or less energy release, as compared with a homogeneous core of the same fuel inventory and the same initial conditions, depending on the gradient of the density worth function at the zonal interface. In some large fast breeder reactors the gradient of the density worth function may be negative at the zonal interface. The positive pressure gradient at the interface during the disassembly phase of a transient results in inwardly directed fuel displacement at the interface and in a positive contribution to the disassembly reactivity feedback. Typically, this can increase the energy released in a disassembly transient by as much as 35%. The effect on energy release of the assumption of fixed fuel density in the fuel equation-of-state was not significant for the transients initiated in the completely molten sodium-free reactor cores studied in this investigation.