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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.
Bingjing Su
Nuclear Science and Engineering | Volume 137 | Number 3 | March 2001 | Pages 281-297
Technical Paper | doi.org/10.13182/NSE01-A2191
Articles are hosted by Taylor and Francis Online.
The numerical stability, equilibrium diffusive limit, and accuracy of the variable Eddington factor (VEF) methods and flux-limited diffusion methods for radiation transport calculations are considered. The diffusive limit analysis proves that three VEF closures and their associated flux-limiters retain full first-order accuracy in the equilibrium diffusion limit while achieving the correct propagation speed in the optically thin streaming limit. The stability analysis reveals that the flux-limited diffusion methods are unconditionally stable, but the VEF equations with an arbitrary nonlinear closure can be numerically unstable for certain commonly used differencing schemes. However, regular solutions to the VEF equations are obtainable by Godunov-type schemes. Numerical comparisons among various solutions for a test problem show that flux-limited diffusion methods are only slightly less accurate than their corresponding VEF methods, and the Minerbo VEF method and the Minerbo flux-limited diffusion method are in general more accurate than other approximations.