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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
F. C. Engel, R. A. Markley, A. A. Bishop
Nuclear Science and Engineering | Volume 69 | Number 2 | February 1979 | Pages 290-296
Technical Paper | doi.org/10.13182/NSE79-A20618
Articles are hosted by Taylor and Francis Online.
Laminar, transition, and turbulent parallel flow pressure drop across wire-wrapped hexagonal rod bundles positioned inside a duct were determined in tests using water, sodium, and air. A smooth transition region from turbulent to laminar flow that occurred over the Reynolds number range from 5000 to 400 characterized the resulting friction factor behavior. The continuous transition region could be explained in terms of the fraction of the flow area in turbulent flow. Laminar friction factors calculated from individual subchannel measurements could be correlated by the same expression found for rod-bundle-averaged conditions. In the laminar range, the friction factor was correlated by the expression f = 110/Re, in the turbulent range by f = 0.55/Re0,25, and in the transition range by where is the intermittency factor. A general laminar flow friction factor correlation was developed: This correlation agrees satisfactorily with limited laminar flow data from rod bundles having different wire-wrap lead pitch-to-diameter ratios.