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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.”
Jean-François Jaeger, Donald J. Dudziak, Giorgio Friedrich, Walter V. Green, Peter Groner, Max Huggenberger, Peter Köhler, P. Marmy, Sandro Pelloni, Jiri Stepanek, Ulrich Stiefel, Peter Stiller, M. Victoria
Fusion Science and Technology | Volume 12 | Number 3 | November 1987 | Pages 364-379
Technical Paper | Blanket Engineering | doi.org/10.13182/FST87-A25069
Articles are hosted by Taylor and Francis Online.
A hybrid blanket for a reversed-field pinch (RFP) reactor is presented for breeding 233U from thorium. This study focuses on the shell/blanket design and assumes a plasma like that used by Culham Laboratory (CL) in its designs. The 233U bred helps the important neutron economy and allows the tritium breeding ratio to be 0.96 at beginning of life for a mean of 1.06 for a 9 MW·yr/m2 burnup. A thick conducting shell is assumed for discharge stability and field reversal. This need for a good conductor requires that only pure copper or aluminum or alloys thereof be used. Two designs were investigated, one with a pure copper first wall/shell, the other with an aluminum alloy. In these designs 3.4% of the thorium is converted to 233U. This corresponds to 18.3 tonnes U in both cases for average thermal powers of 4590 and 4450 MW, respectively, at a wall loading of 2.2 MW/m2 during the burn phase. The breeding rates of 233U are, respectively, 0.66 and 0.69 kg/MW·yr, representing ratios of fission events per bred atom of 0.26 and 0.22, which is naturally better than in the fast breeder. In both designs the low metallurgie temperature limit means the large amount of power deposited on and in the shell is not attractive thermodynamically. The resulting large temperature differences in the shell cause high mechanical stresses. The design as it stands is not feasible from the point of view of radiation damage to materials. The pure metal copper shell swells too much (life limit 1.3 to 2 MW·yr/m2), the transmutations limit the electrical life to 3 MW·yr/m2, and low alloys of copper have not yet been irradiated tofluences sufficient for consideration. The aluminum alloy becomes brittle. This and low cycle fatigue each limit the life to 4.5 MW·yr/m2. Further thoughts at CL show that the RFP should work with a thinner shell as well; this would considerably reduce the thermal stresses in the shell and increase its lifetime sufficiently.