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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.”
Vikram Singh, Matthew R. Lish, Alexander M. Wheeler, Ondřej Chvála, Belle R. Upadhyaya
Nuclear Technology | Volume 202 | Number 1 | April 2018 | Pages 15-38
Technical Paper | doi.org/10.1080/00295450.2017.1416879
Articles are hosted by Taylor and Francis Online.
A nonlinear dynamic model for the two-fluid molten-salt breeder reactor (MSBR) system is presented. This work is partly inspired by a preliminary dynamic model of the concept studied at Oak Ridge National Laboratory (ORNL). The core heat transfer model has been revised to accurately reflect the design exemplified in ORNL-4528—the last report on the two-fluid design. A brief description of the reactor system and the effects of reactor poisons and a discussion of temperature feedback mechanisms are presented. This background information is followed by an overview of the modeling approach and a discussion of the revised lumped parametrization, along with detailed descriptions of the modeling methodology and model limitations. All equations and parameters used in the model are presented to aid in model reproduction and adaptation for other molten-salt reactor designs. Model stability is analyzed by observing the uncontrolled response to reactivity perturbations. Simulations illustrate stable behavior at all power levels investigated. Temperature-induced feedback effects lead to stable dynamics for both large and small reactivity transients. Stable and smooth changes in the various nodal temperatures are also observed. The frequency response of the system indicates no dynamics problems at all operating power levels and is consistent with the transient response. Characteristic features in the frequency response plots due to feedback effects are also discussed. Finally, the load-following capability of the MSBR system is studied for various ramp rates of the power demand in the final heat sink. The temperatures in all salt-containing parts of the system are observed to vary about an average during the load-following maneuver. It is observed that the MSBR system exhibits a self-regulating behavior, minimizing the need for external controller action for load-following operations.