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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Toshikazu Takeda, Hironobu Unesaki, Toshihisa Yamamoto, Katsuya Kinjo, Toshio Sanda
Nuclear Science and Engineering | Volume 101 | Number 2 | February 1989 | Pages 179-184
Technical Paper | doi.org/10.13182/NSE89-A23606
Articles are hosted by Taylor and Francis Online.
Neutron streaming in a fast breeder reactor fuel subassembly caused by the double heterogeneity of the pin structure and the wrapper tube structure is estimated by double heterogeneous modeling. The neutron streaming is decomposed into three components: the pin-cell heterogeneity, the wrapper tube heterogeneity, and the homogenized fuel/wrapper tube subassembly effect. The streaming effect is evaluated based on the Benoist diffusion coefficient. The total streaming effect caused by the double heterogeneity structure of a fuel subassembly is found to be about −0.2% Δk/kk′ for keff, which is almost twice that obtained from the conventional pin-cell model of about −0.1% Δk/kk′.
