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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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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.
T. Ginsberg, D. M. France
Nuclear Science and Engineering | Volume 48 | Number 1 | May 1972 | Pages 103-114
Technical Paper | doi.org/10.13182/NSE72-A22460
Articles are hosted by Taylor and Francis Online.
Temperature distributions in an idealized nuclear fuel assembly were computed and studied parametrically. The assembly, which consists of a square array of spacer-free fuel elements, is bounded by an assembly wall and is cooled by longitudinal liquid metal flow. A single-region multicell analysis is used to predict the influence of the fuel assembly wall on the temperature distributions and Nusselt numbers in the idealized assembly. An analytical series solution method couples adjacent cellular temperature-field solutions, and boundary conditions on these and other irregular boundaries are satisfied using a least-squares matching technique. Two slug flow coolant models are considered in the analysis. A global slug flow model assumes a uniform coolant velocity. A cellular slug flow model assigns to each cell a velocity based on its hydraulic diameter. Results of this analysis show that the temperature distributions across the fuel assembly and around each individual fuel element are most strongly influenced by the cellular mass flow rate distribution, which is characterized by a single parameter—the cellular mass flow rate ratio. Fuel assembly temperature gradients are minimized if this ratio is chosen equal to unity. Computations of cellular Nusselt numbers indicate that while steep thermal gradients may exist across the fuel assembly, the Nusselt numbers of all but the cell closest to the wall are unaffected by the presence of the wall. Cellular Nusselt numbers, cellular coolant bulk temperatures, and fuel-element wall temperatures are presented for a range of pitch-to-diameter and cellular mass flow rate ratios.