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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.”
Jacopo Buongiorno, James W. Sterbentz, Philip E. MacDonald
Nuclear Technology | Volume 153 | Number 3 | March 2006 | Pages 282-303
Technical Paper | Fission Reactors | doi.org/10.13182/NT06-A3708
Articles are hosted by Taylor and Francis Online.
The supercritical water-cooled nuclear reactor (SCWR) concept offers potential for superior economics due to its high thermal efficiency and plant simplification. However, design of a thermal-spectrum core for such a reactor is complicated by the relatively low density of the water coolant and therefore reduced moderation. This requires the SCWR design to include a dedicated moderator. One solution explored worldwide is based on the use of water rods. In this paper we assess the feasibility of a different approach based on solid moderators, which has some potential advantages including increased core thermal capacity, reduced coolant worth, and simplified vessel internals. The neutronic performance of several solid moderators was evaluated and compared to that of water rods. It was found that the only acceptable solid moderator is zirconium hydride. Axial and local peaking can be readily suppressed by modest variations of the enrichment in a manner similar to the boiling water reactor practice. The Doppler and coolant reactivity coefficients are both negative and in the range of light water reactor experience. The use of zirconium hydride as a stable structural core component was evaluated and found to be acceptable under steady-state and accident conditions. In addition to its chemical and mechanical stability, zirconium hydride can also be fabricated with existing technology. However, its impact on the SCWR cost of electricity generation is deemed significant.