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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.”
B.D. Boyer, J. W. Hartzell,† S. Lider, G. E. Robinson, A. J. Baratta, A. J. Roscioli
Nuclear Technology | Volume 103 | Number 2 | August 1993 | Pages 206-219
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT93-A34844
Articles are hosted by Taylor and Francis Online.
The effects of condensation steam quenching in modeling two-phase flow phenomena during a nuclear reactor transient are studied. The RETRAN-02-MOD002 code, with three field equations and a nonequilibrium pressurizer model option, and the TRAC-BF1 code, with six field equations, predicted plant response to a boiling water reactor plant test of a main steam isolation valve closure without safety relief valve opening. The basic RETRAN-02-MOD002 field equations cannot model steam quenching by condensation. However, by activating the nonequilibrium modeling option of the basic RETRAN-02-MOD002 code and by inputting appropriate interfacial heat transfer coefficients, steam quenching by condensation was calculated. This approach gave results closer to those obtained with the test data. The two TRAC-BFI models used two different methods of tracking water level to approximate the condensation quenching effect. Because the void fraction changes too gradually, the calculation without the TRAC two-phase water level tracking option overquenched the pressure and filled the vessel with too much water. However, because the void fraction changes virtually instantaneously (as it does in the plant), the TRAC two-phase water level tracking option’s prediction of the quenching of the pressure was 50% closer to the data than was any RETRAN-02-MOD002 calculation, and it followed the water level almost as well as the RETRAN-02-MOD002 best-estimate case. Both codes overpredicted the pressure spike.