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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.”
Shisheng Wang, Andrei Rineiski, Liancheng Guo
Nuclear Technology | Volume 196 | Number 3 | December 2016 | Pages 588-597
Technical Paper | doi.org/10.13182/NT16-5
Articles are hosted by Taylor and Francis Online.
The lumped heat transfer methodology is simple, and the solution is very fast, so the lumped parameter approach has been widely used in thermal-hydraulic analysis for fuel pin heat transfer in nuclear reactors. In the conventional lumped thermal analysis of fuel pin structure, each component (such as a pellet, gap, cladding, etc.) is characterized by a concentrated bulk temperature (or averaged temperature), and a bulk thermal resistance. In contrast to this conventional lumped thermal resistance model, in this paper another kind of lumped thermal resistance heat transfer model for fuel pin structure has been developed. In this model, each fuel pin component is still represented by a concentrated lumped mean temperature node, while the location of the mean temperature position of each component is no longer set on the geometrical midpoint center; rather, it is assigned exactly onto the analytical temperature profile. Two thermal resistance elements are assigned for each component in this new model; between each component surface and its associated lumped mean temperature node a thermal resistance is assigned. Heat conduction in the radial direction between the mean temperature nodes of different components is purposely defined to take place at the in-between surface nodes. With this new arrangement, the location of the mean temperature positions for each component can be determined analytically, and all the thermal resistances are redefined, accordingly. The advantage of the presented method is that the temperature profile in the whole pin at any radial position can be reconstructed after a quite easy lumped heat transfer calculation. This advanced methodology can be used in nuclear reactor simulation studies where the fastness of the solution is of concern. It is of great advantage, e.g., for the early prediction of the formation of an internal molten fuel cavity within a fuel pin using this temperature profile, before the lumped pellet average temperature reaches the fuel melting point. This lumped thermal resistance model can be readily used for the sodium-cooled fast reactor design, especially for the optimized design of the pin structure. It can be also extended to the restructured fuel pin through the way that each restructured zone is treated as an individual component, e.g., for taking into account temperature-dependent thermophysical properties.