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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.”
S. Kliem, S. Danilin, A. Hämäläinen, J. Hádek, A. Keresztúri, P. Siltanen
Nuclear Science and Engineering | Volume 157 | Number 3 | November 2007 | Pages 280-298
Technical Paper | doi.org/10.13182/NSE07-A2728
Articles are hosted by Taylor and Francis Online.
Recently, three-dimensional neutron-kinetics core models have been coupled to advanced thermal-hydraulic system codes. These coupled codes can be used for the analysis of the whole reactor system. In the framework of the international association Atomic Energy Research (AER) on VVER Reactor Physics and Reactor Safety, two benchmarks for these code systems were defined. The reference reactor is the Russian VVER-440. The response of the reactor core to a symmetric and an asymmetric main steam line break should be investigated. So, different aspects of the coupling could be tested. As an additional feature, the participants had to use their own nuclear data.Each of these benchmarks was calculated by five different code systems. The comparison of the received solutions for the symmetric case shows good agreement in the evolution of the thermal hydraulics. When the core power reestablishes after recriticality, differences between the single solutions develop, mainly connected with the use of different nuclear data. Because of the increased complexity of the calculations, in the second benchmark differences between the thermal-hydraulic behavior in the single calculations were observed, additionally. These differences have their main origin in the behavior of the secondary side.The results of both benchmarks show the safety potential of the VVER-440 reactor. Even under very conservative conditions, no fuel rod failure was determined by the calculations, and the reactor was transferred into a subcritical final state.