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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.”
Michitsugu Mori
Nuclear Technology | Volume 121 | Number 3 | March 1998 | Pages 260-274
Technical Paper | RETRAN | doi.org/10.13182/NT98-A2838
Articles are hosted by Taylor and Francis Online.
The benchmarking and qualification analyses of RETRAN-03 (RETRAN-3D) for boiling water reactor (BWR) stability analyses were carried out by comparison with the frequency-domain stability analysis code NUFREQ-NPT with the stability test data of the Peach Bottom Unit 2. The sensitivities of model parameters were studied in terms of the type of equation model, vapor-liquid interface heat transfer coefficient in upper downcomer, method of characteristics (MOC) model, proportionality constant in the pressure change mass transfer term, and nodalization of a core for the turbine trip test analyses. The sensitivity studies of the model parameters to the decay ratio in stability analyses were performed on the number of core channels, type of equation model, nodalization of a core, perturbation type of disturbance, slip model, proportionality constant in the pressure change mass transfer term, Courant number, MOC model, and kinetics model. The models were selected for the turbine trip tests analyses and for stability tests analyses, based on the sensitivity studies. The model used to analyze stability in RETRAN-03 adopted the five-equations with the MOC, and two-channel models for the core heating region divided into 40 nodes despite 24 nodes used for the turbine trip test analyses. The validation of the model was confirmed by the analyses of the turbine trip tests of the Peach Bottom Unit-2. The stability analyses with the test data and the benchmarking of RETRAN-03 compared with the frequency-domain stability analysis code NUFREQ-NPT in BWR stability exhibit verification and validation within the applicable limitation of the code.
