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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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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. Andersson, D. Blanchet, H. Nylén, R. Jacqmin
Nuclear Science and Engineering | Volume 185 | Number 2 | February 2017 | Pages 263-276
Technical Paper | doi.org/10.1080/00295639.2016.1272358
Articles are hosted by Taylor and Francis Online.
In axially heterogeneous fast reactor concepts, such as the Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID) CFV (French acronym of Coeur à Faible effet de Vide sodium, meaning low sodium void effect core) core, the accurate neutronic prediction of control rods is a challenge. In such cores, the performance of the classical two-dimensional (2-D) equivalence procedure, used for control rod homogenization in homogeneous fast reactors, is questionable.
In this work (part I of two companion papers), a number of axially heterogeneous environments, representative of a CFV-type core, are investigated using 2-D (X-Z) models, with the objective to distinguish regions where the classical equivalence procedure is valid from those where it is not.
It is found that the environments that affect the control rod absorber the most, and are likely to invalidate the procedure, are the internal control rod interfaces, such as the absorber/follower interface and the interface between zones of different boron enrichments. The range of the main spectral impact could be seen within 0 to 10 cm from the material interfaces studied.
In the companion paper (part II), a full-core investigation is performed that builds upon the results of this paper.