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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Latest News
EPA administrator Lee Zeldin talks the future of nuclear
In a recent interview on New York radio station 77 WABC, administrator of the Environmental Protection Agency Lee Zeldin talked with host John Catsimatidis about the near-term future of the domestic nuclear industry and the role the EPA will play in the sector.
Catsimatidis kicked off the interview by asking if the U.S. will be able to reach total energy independence. Zeldin responded by saying that decreasing energy dependence on other countries, especially adversaries, was a top priority for him and the Trump administration.
Rahman S. Almusafir, Ahmed A. Jasim, Muthanna H. Al-Dahhan
Nuclear Science and Engineering | Volume 197 | Number 6 | June 2023 | Pages 1001-1037
Critical Review | doi.org/10.1080/00295639.2022.2146993
Articles are hosted by Taylor and Francis Online.
Knowledge and proper safety analyses of the gas coolant and heat transport mechanism in the dynamic core of packed pebble bed nuclear reactors pose challenges to the reliable design and efficient operation of these reactors. Therefore, this paper carefully reviews most of the gas coolant mixing and heat transport studies performed for the fluid flow and heat transfer processes in packed pebble bed reactors (PBRs). It begins with a brief introduction and description of nuclear PBRs. The second section summarizes the physical characteristics of packed bed reactors in terms of the bed structure (porosity) and its radial and axial distributions. The next section examines in detail the characteristics of fluid flow in terms of flow regime identification and pressure drop measurements and correlations. The fourth section considers the investigations and quantifications of the gas dispersion and mixing phenomena of packed bed reactors. The next section deals with the current state of the heat transfer characteristics, measurements, and predictions including both empirical correlations and semiempirical model-based studies. Tables summarize the reported experimental studies along with their operating condition ranges. Comprehensive comparisons with the empirical correlations and available models are presented with significant findings. The content and findings of the present work could provide a thorough understanding and useful information and advance knowledge of the pressure drop, gas coolant mixing, and convective heat transport phenomena in packed pebble bed nuclear reactors.