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Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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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.”
J. D. Rader, M. S. Greenwood, A. M. Melin, A. J. Wysocki (ORNL), G. M. Borza C. D. Lietwiler (SMR Inventec, LLC)
Proceedings | Nuclear Plant Instrumentation, Control, and Human-Machine Interface Technolgies (NPIC&HMIT 2019) | Orlando, FL, February 9-14, 2019 | Pages 765-775
A cooperative research and development agreement between Oak Ridge National Laboratory (ORNL) and Holtec International subsidiary SMR Inventec, LLC, was crafted to explore the primary flow stability of the SMR-160, a natural circulation-based pressurized-water small modular reactor. It is necessary to investigate the stability of the system at operational power levels when natural circulation is the driver of the primary flow to show that operation of the plant is stable, predictable, and controllable. The first phase of the analysis was a code-to-code benchmarking activity between RELAP5-3D and the Modelica-based, ORNL-developed TRANSFORM library. The benchmarking included both generic comparisons of heated channels and step-change transients of certain plant boundary conditions of interest. Following the benchmarking, a parametric series of linear stability tests was performed using discrete signals applied to one of several boundary conditions. These signals excite the natural harmonics of the system and produce small perturbations in the power of the reactor. Though some resonant behavior was observed, the results indicate stable operation of the SMR-160 at the conditions investigated. The frequency range covered included several octaves on either side of the loop transit frequency. Thus, a reasonable determination of the stability and controllability of the plant can be made over a large range of timescales.