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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
2027 ANS Winter Conference and Expo
October 31–November 4, 2027
Washington, DC|The Westin Washington, DC Downtown
Standards Program
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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Latest News
Supreme Court rules against Texas in interim storage case
The Supreme Court voted 6–3 against Texas and a group of landowners today in a case involving the Nuclear Regulatory Commission’s licensing of a consolidated interim storage facility for spent nuclear fuel, reversing a decision by the 5th Circuit Court of Appeals to grant the state and landowners Fasken Land and Minerals (Fasken) standing to challenge the license.
David A. Petti, James P. Adams, James L. Anderson, Richard R. Hobbins
Nuclear Technology | Volume 87 | Number 1 | August 1989 | Pages 243-263
Technical Paper | TMI-2: Materials Behavior / Nuclear Safety | doi.org/10.13182/NT89-A27652
Articles are hosted by Taylor and Francis Online.
An analysis of fission product release during the Three Mile Island Unit 2 (TMI-2) accident has been performed to provide an understanding of fission product behavior that is consistent with both the best-estimate accident scenario and fission product results from the sample acquisition and examination efforts. “Firstprinciples” fission product release models are used to describe release from intact, disrupted, and molten fuel during the various phases of the TMI-2 accident. Extensive gaseous and volatile fission product release is calculated to have occurred, with local regions of the core experiencing up to 100% release. Diffusion is calculated to have dominated release during the initial core heatup, while bubble coalescence and rise dominated release from the large consolidated region of molten material. The calculations are generally consistent with fission product retention data from upper and lower plenum debris bed samples. An exception to this is the small retention of cesium in the lower plenum samples, suggesting that cesium may have been in a low-volatile chemical form. The small release fractions measured for the less volatile fission product oxides (SrO, Eu2O3, and Ce2O3) are calculated to have resulted from the low partial pressures of these species in the melt coupled with the low surface-to-volume ratio of the consolidated melt region. Metallic species (ruthenium and antimony) are thought to be associated with metallic core structural material debris.
