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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.
William T. Sha, Alan E. Waltar
Nuclear Science and Engineering | Volume 44 | Number 2 | May 1971 | Pages 135-156
Technical Paper | doi.org/10.13182/NSE71-A19663
Articles are hosted by Taylor and Francis Online.
A two-dimensional (R - Z) integral model for characterizing fast reactor excursions from accident inception through core disassembly is presented. For predisassembly calculations, a Eulerian geometric model is used and multichannel heat-transfer computations are performed. Reactivity feedback due to Doppler broadening, coolant density change and voiding, and fuel movement are taken into account. A Lagrangian coordinate system is used in the disassembly phase, wherein the neutronics balance consists of Doppler broadening and material motion. A unique feature of the model is the ability to accommodate a pointwise Energy-Density-Dependent Equation-of-State according to the local sodium inventory that actually exists at the time of disassembly. By providing a consistent basis for establishing the effective reactivity ramp rate, Doppler coefficient, appropriate Equation-of-State, and temperature distribution at the start of core disassembly, much of the arbitrariness normally associated with large accident analyses can be removed. For most accident analyses, this model predicts a significantly lower energy yield during a superprompt critical nuclear excursion than would be computed by using the conventional modified Bethe-Tait analysis.