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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.
M. J. Ades, K. L. Peddicord
Nuclear Science and Engineering | Volume 81 | Number 4 | August 1982 | Pages 563-569
Technical Note | doi.org/10.13182/NSE82-A21448
Articles are hosted by Taylor and Francis Online.
An analytical method is presented to estimate the effective thermal conductivity of sphere-pac fuel during restructuring. This method is based on a unit cell model in which a sintering model is used to describe the extent of restructuring occurring between the fuel particles. As a result of sintering, a “neck” is formed between the fuel spheres. The effective conductivity of the sphere-pac bed can then be evaluated in terms of restructuring, i.e., as a function of temperature and necking between the fuel spheres. The effects of other relevant parameters such as the gas pressure in the sphere-pac pin and fission gas release are also included in the model Furthermore, a thermal conductivity criterion is used to determine the matching conductivity boundary, which is defined as the outer radial boundary where fuel restructuring is completed. Fuel restructuring is of particular importance in sphere-pac fuel because of its controlling effect on the temperature distribution. By knowing the effective conductivity, the temperature distribution of the fuel, both in its initial configuration and during restructuring, can be determined. Using the model, the temperature distribution as well as the extent of restructuring can be calculated. This model can be incorporated into computer codes to predict the overall thermal and mechanical performance of sphere-pac fuel pins.