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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
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.