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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.”
Roberto Orsi
Nuclear Science and Engineering | Volume 154 | Number 2 | October 2006 | Pages 247-259
Computer Code Abstract | doi.org/10.13182/NSE06-A2631
Articles are hosted by Taylor and Francis Online.
The finite difference approach poses a major problem of keeping the exact values of material zone areas and volumes in any geometric simulation for transport calculations. When this requirement is not thoroughly fulfilled, updating density values may be necessary to conserve material zone masses. A method is described that conserves the mass of geometrically complex material zones simulated on both Cartesian and cylindrical mesh grids and its implementation in BOT3P5.0, which is the latest version of the BOT3P code package, publicly and freely available from the Organization for Economic Cooperation and Development/Nuclear Energy Agency Data Bank. BOT3P5.0 lets users optionally require as refined a computation as desired of the possible area and volume error of material zones due to the stair-cased geometry representation and automatically corrects material densities to globally conserve masses. BOT3P5.0 optionally stores on binary outputs the detailed material zone distribution map inside each cell of the mesh grid according to a submesh grid refinement defined in input by the user and the area and volume fraction distribution of the different material zones contained in meshes at zone interfaces. That also allows a local (per-cell) density correction as an alternative to the approach of a uniform density correction on the whole zone domain and makes it possible to perform material zone homogenization locally and transport analyses more accurately.