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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.
T. K. Larson, R. A. Dimenna
Nuclear Science and Engineering | Volume 100 | Number 1 | September 1988 | Pages 21-32
Technical Paper | doi.org/10.13182/NSE88-A29011
Articles are hosted by Taylor and Francis Online.
Preservation of similitude criteria in current mathematical models used for transient analysis of thermal-hydraulic systems is discussed. Input models for the RELAP5 computer code were developed at the Idaho National Engineering Laboratory for two simple hypothetical natural circulation systems consisting of a closed loop containing energy generation, energy removal, and flow resistance. The two models differed significantly in geometric scale size. A reference model had components and operating conditions in a range similar to those found in typical nuclear steam supply systems; a scaled model, geometrically much smaller than the reference model, had components that were sized from the reference model using similarity criteria presented in the literature. Steady-state and transient single- and two-phase natural circulation calculations were conducted using both models to determine if the model-to-model relationships in time, pressure drop, and velocity scales were in accordance with the similitude criteria. Results indicate that, while the code predicts the expected fundamental effects of geometric scale, there are noteworthy differences in the details of calculations.