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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.”
Yanheng Li, Wei Ji
Nuclear Science and Engineering | Volume 173 | Number 2 | February 2013 | Pages 150-162
Technical Paper | doi.org/10.13182/NSE12-13
Articles are hosted by Taylor and Francis Online.
In pebble bed reactors (PBRs), pebble flow and coolant flow are highly correlated, and the behavior of each flow is strongly influenced by pebble-coolant interactions. Simulation of both flows in PBRs presents a multiphysics computational challenge because of the strong interplay between the flows. In this paper, a fully coupled multiphysics model is developed and applied to analyze the pebble flow and coolant flow in helium gas-cooled and fluoride salt-cooled PBR designs. A discrete element method is used to simulate the pebble motion to obtain the distribution of pebble density and velocity and the maximum contact stress on each pebble. Computational fluid dynamics is employed to simulate coolant dynamics to obtain the distribution of coolant velocity and pressure. The two methods are fully coupled through the calculation and exchange of pebble-coolant interactions at each time step. Thus, a fully coupled multiphysics computational framework is formulated. A scaled experimental fluoride salt-cooled reactor facility and a full-core helium gas-cooled HTR-10 reactor are simulated. Noticeable changes, such as higher pebble density in the cylindrical core region and more uniform vertical fluid speed profile due to the coupling effect, are observed compared to previous single-phase simulations alone without coupling. These changes suggest that the developed computational framework has higher fidelity compared with previous uncoupled methodology in analyzing pebble flow in PBRs. For the scaled experimental fluorite salt-cooled reactor facility calculation, similar hydraulic loss can be obtained as measured in the University of California, Berkeley, Pebble Recirculation Experiment (PREX), demonstrating the potential of the developed method in thermal-hydraulic analysis for PBRs.