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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.”
Bernard R. Bandini, Kostadin N. Ivanov, Anthony J. Baratta, Robert G. Steinke
Nuclear Technology | Volume 123 | Number 1 | July 1998 | Pages 1-20
Technical Paper | Reactor Safety | doi.org/10.13182/NT98-A2875
Articles are hosted by Taylor and Francis Online.
The verification of a three-dimensional nodal transient neutronics routine in the TRAC-PF1/MOD3 Version 1.0 thermal-hydraulic system analysis computer code is discussed. This neutronics algorithm is based on a fully implicit transient version of the well-known nodal expansion method. Results from running TRAC-PF1/MOD3 with this new neutronics routine were compared with the results of running two established neutronics/thermal-hydraulic space-time codes, HERMITE and ARROTTA. The transient chosen for this code verification was a rapid ejection of an off-center control rod in a Westinghouse pressurized water reactor, which is initially at hot standby. This severe prompt-critical transient provides a stringent test of TRAC-PF1/MOD3's new multidimensional neutronics routine and its coupling to the existing thermal-hydraulic solution methodology. Because of its speed, the transient tests only the fuel rod heat conduction coupling and not the coolant thermal-hydraulic coupling.Acceptable agreement was obtained among the results from TRAC-PF1/MOD3, HERMITE, and ARROTTA during all phases of this transient. Agreement was in the areas of time dependence of total-core and peak-assembly powers, as well as the time dependence of the core-average and peak-assembly fuel temperatures. In addition, comparison of several steady-state calculations that provide initial conditions for the transient analysis showed acceptable agreement in the calculated eigenvalues and normalized assembly-power distributions.