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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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.”
Gabriel Kooreman, Farzad Rahnema
Nuclear Technology | Volume 192 | Number 3 | December 2015 | Pages 264-277
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT14-150
Articles are hosted by Taylor and Francis Online.
The hybrid Diffusion-Transport Homogenization (DTH) method has been improved by replacing the assembly-level fixed-source calculation step with a fixed number of whole-core transport sweeps following each homogenization step. Like the unmodified DTH method, the Enhanced hybrid Diffusion-Transport Homogenization (EDTH) method adds an “auxiliary cross-section” term to the right side of the transport equation in order to maintain consistency with the heterogeneous equation. As an improvement to the DTH method, the on-the-fly rehomogenization step of the EDTH method utilizes a fixed number of full-core transport sweeps in lieu of assembly-level fixed-source heterogeneous transport calculations. The EDTH method has been tested in one-dimensional reactor core benchmark problems typical of a boiling water reactor core, a gas-cooled thermal reactor [High Temperature Test Reactor (HTTR)] core, and a pressurized water reactor core with mixed-oxide fuel. The method has been shown to reproduce the heterogeneous transport flux profile with 0 to 46 pcm eigenvalue error and 0.1% to 1.8% mean relative flux error with a speedup factor of 1.4 to 4.5 times faster than the DTH method. This represents a speedup of 3.0 to 12.5 times compared to fine-mesh transport.
