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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.
Sudip S. Dosanjh, Martin Pilch
Nuclear Science and Engineering | Volume 108 | Number 2 | June 1991 | Pages 172-183
Technical Paper | doi.org/10.13182/NSE91-A23815
Articles are hosted by Taylor and Francis Online.
During hypothetical severe nuclear reactor accidents, structural materials in the reactor vessel can relocate downward and form debris regions above the lower head. A one-dimensional model is presented that considers melt progression in the debris as well as the thermal and mechanical response of the head. Only creep rupture of the lower head is considered; however, other modes of vessel failure can be considered with the methodology developed, and the model can easily be extended to higher dimensions. Numerical solutions are compared with an analytical model developed by T G. Theofanous. The goal of the work is to identify the parameters that most affect the state of the debris at the time of lower head creep rupture. Results of sensitivity analyses presented indicate that melt relocation phenomena, the initial composition profile of the debris, and the pressure inside the vessel are all important. On the other hand, changing the porosity or the particle diameter produces less significant effects because several competing phenomena cancel each other.