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ANS Student Conference 2025
April 3–5, 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.”
Mohamed S. El-Genk, Sung-Ho Kim, Galal M. Zaki, Jeffrey S. Philbin, James F. Schulze, Fabian C. Foushée
Nuclear Technology | Volume 76 | Number 3 | March 1987 | Pages 360-369
Technical Paper | Nuclear Safety | doi.org/10.13182/NT87-A33921
Articles are hosted by Taylor and Francis Online.
To investigate the coolability of a uniformly heated tube by free convection of atmospheric air, heat transfer experiments were conducted using vertical open an-nuli with adiabatic outer walls. To examine the effect of the annulus ratio on the coolability of the heated tube, the experiments employed four annuli (diameter ratios of 1.155, 1.33, 1.63, and 12.0). The operating parameters included heat fluxes up to 1.38 W/cm2 with a corresponding surface temperature of 856K. The results, extrapolated to 1200 K, were used to provide a qualitative estimate of the coolability of multirod bundles, as a function of the equilibrium surface temperature and the pitch-to-diameter (P/D) ratio. Although the decay heat removal rate for P/D values <1.5 increased rapidly with P/D ratio, for larger P/D values the decay heat removal rate was insensitive to either the P/D value or the rod arrangement in the bundle. These results suggest that in TRIGA-type reactors at a typical P/D ratio of 1.12, the maximum decay heat removal level is ∼1 kW/m. This maximum corresponds to an initial decay power following sustained operation at ∼12.5 kW/m.