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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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.”
Suxia Hou, Fuyu Zhao, Yun Tai, Liu Cheng
Nuclear Technology | Volume 169 | Number 2 | February 2010 | Pages 126-133
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT10-A9357
Articles are hosted by Taylor and Francis Online.
Two-phase flow instability in parallel channels of a once-through steam generator (OTSG) is systematically analyzed by the modern frequency domain method. The mathematical expressions of heat transfer and flow for an OTSG are proposed, and the transfer function of the closed-loop system is deduced by the use of linearization and Laplace transfer. The OTSG's stability is judged according to the Nyquist Stability Criterion. The instability of OTSG in two cases (single-channel model and multichannel model) is researched, respectively, for a numerical example. The result shows the classical frequency domain method can be commonly used when the coupling effects in the system are negligible, and it is only a special case of the multivariable method. Furthermore, the stability sensitivity to the operating parameters is analyzed for the OTSG in this paper. The predicted results are in agreement with the experimental results given in the literature.
