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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
Bilge Ozgener
Fusion Science and Technology | Volume 61 | Number 1 | January 2012 | Pages 308-313
Modeling and Simulations | Proceedings of the Fifteenth International Conference on Emerging Nuclear Energy Systems | doi.org/10.13182/FST12-A13438
Articles are hosted by Taylor and Francis Online.
Discrete ordinates solutions of the neutron transport equation require the solution of the within-group transport equation by the method of iteration on the scattering source. Scattering source iterations are hampered by extremely slow convergence rates when the medium is highly scattering. Among the methods proposed for the acceleration of the scattering source iterations, the coarse mesh rebalance and the diffusion synthetic acceleration techniques appear to be the most prominent ones. Thus, one or the other has been adopted in most of the SN codes. The numerical studies concerning the effectiveness of these acceleration methods have been made mostly for the planar geometry. There are some studies also for the multidimensional Cartesian geometries. In this study we have tried to assess the merits of these acceleration techniques in a curvilinear coordinate system that is spherical geometry. The performance of both of the acceleration methods have been determined by varying the scattering to total cross section ratio, the mesh size, the degree of anisotropy in scattering for a uniform spherical system. Then the study is extended to multiregion systems some of which are diffusive and in some of which transport effects are important.
