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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.”
T. Auerbach
Nuclear Science and Engineering | Volume 46 | Number 1 | October 1971 | Pages 61-75
Technical Paper | doi.org/10.13182/NSE71-A22336
Articles are hosted by Taylor and Francis Online.
The purpose of this paper is to determine the multigroup neutron flux in cells of finite, regular, unreflected, square lattices. The dependence on buckling and on cell squareness is shown explicitly for the moderator spectrum only. The corresponding fuel spectrum at each lattice site may be obtained readily from the condition of flux continuity. Heterogeneous theory of the source-sink type forms the starting point of the present theory. It is shown that each integration constant appearing in the heterogeneous solution for a finite periodic lattice separates into a product of two constants, one of which is a purely geometrical factor of position xi,yi of the i’th element, while the other is a purely physical constant depending on the physical characteristics of the lattice alone. Knowledge of the position dependence allows the flux in a square cell of a finite system to be determined for all multipole orders by means of summation techniques. The physical constants are obtained from multipole moderator-to-fuel boundary conditions. These conditions are expressed in terms of response coefficients and result in a set of equations from which the position dependence is again eliminated by means of summation techniques. The result is a set of simultaneous equations for the physical constants alone which can be solved once the criticality condition is satisfied. The number of these equations is independent of the number of elements in the lattice and equals twice the number of multipoles times the number of energy groups.