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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
M. A. Hassan, K. Rehme
Nuclear Technology | Volume 52 | Number 3 | March 1981 | Pages 401-414
Technical Paper | Fuel Cycle | doi.org/10.13182/NT81-A32714
Articles are hosted by Taylor and Francis Online.
The influence of spacer grids on the heat transfer in gas-cooled rod bundles was determined experimentally for the first time over a wide range of parameters. The experimental investigations were carried out with a smooth and a rough rod bundle for Reynolds numbers between 600 and 2 × 105. The measured range of Reynolds numbers covered the transition from laminar to turbulent, the transition from hydraulically smooth to rough, and fully rough flows. In gas cooling, artificial roughnesses on the rod surfaces are used to disturb the viscous sublayer, which acts as an insulator because of the low thermal conductivity of gases. For this investigation, a two-dimensional rectangular roughness was used, which had an optimum heat transfer characteristic. The blockage factor ∊ was varied between 25 and 35%. These values are typical of flow blockages due to spacer grids in gas-cooled fast reactors. The measurements were carried out from 10 Dh upstream to 33 Dh downstream of the spacer grid. The measured range covered the zone of heat transfer influenced by the spacer grid. The measurements showed heat transfer to be improved by spacer grids in all cases investigated. On the basis of the measurements, empirical correlations could be established for the influence of the spacer grid on heat transfer in terms of the measured parameters, i.e., Reynolds number, blockage factor, and the type of heat transfer surface. These empirical correlations can be directly used in computer codes for analysis of the thermodynamics and fluid dynamics of gas-cooled rod bundles.