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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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Latest News
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.
D. M. France, T. Ginsberg
Nuclear Science and Engineering | Volume 51 | Number 1 | May 1973 | Pages 41-51
Technical Paper | doi.org/10.13182/NSE73-A23256
Articles are hosted by Taylor and Francis Online.
An analytical study was performed to investigate the utility and accuracy of the lumped parameter approach to heat transfer analysis in a nuclear reactor subassembly. It is shown that the lumped parameter approach is a useful mathematical method if the appropriate heat transfer length scales associated with diffusion heat transfer are employed. Important results of this study supporting the utility of the lumped parameter approach indicate that in the parameter range of interest the length scales are geometry-dependent only. They are shown to be independent of radial power distribution across the subassembly, and asymptotic values which are equal to length scales corresponding to the thermally fully developed condition may be used in the thermally developing entry region which encompasses the entire axial length of typical nuclear reactor subassemblies. Two characteristic length scales are presented and may be easily applied in lumped parameter steady-state heat transfer calculations in spacer-free triangular arrays of nuclear fuel elements within the range of parameters of interest for nuclear reactor applications. These length scales apply to fuel rods adjacent and nonadjacent to subassembly walls, respectively.