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ANS Student Conference 2025
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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.”
Surendra Mishra , R. S. Modak, S. Ganesan
Nuclear Science and Engineering | Volume 170 | Number 3 | March 2012 | Pages 280-289
Technical Paper | doi.org/10.13182/NSE10-84
Articles are hosted by Taylor and Francis Online.
Large-sized pressurized heavy water reactors (PHWRs) are neutronically loosely coupled and hence are prone to significant changes in flux shape during operation. As a result, they need a sophisticated regulation procedure based on an online flux mapping system (OFMS). During the reactor operation, neutron flux is continuously measured at certain predetermined in-core locations. The purpose of OFMS is to compute a detailed flux map at all points in the reactor, after every 2 min, by making use of the measured fluxes. The knowledge of detailed flux distribution is then used for an appropriate regulating action. The choice of computational method used by OFMS is of crucial importance because the method is expected to be both efficient and accurate and should work for a range of reactor configurations occurring during the operation. In this paper, three different methods, namely, flux synthesis, internal boundary condition, and combined least squares (CLSQ), are analyzed for their prospective use in the forthcoming 700-MW(electric) Indian PHWR. The CLSQ method is found to be most accurate, although it needs significant computation. A hybrid method that combines certain features of other methods is also studied and seems to give good accuracy with moderate computational effort.