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Division Spotlight
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
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.
G. C. Pomraning, A. K. Prinja, J. W. VanDenburg
Nuclear Science and Engineering | Volume 112 | Number 4 | December 1992 | Pages 347-360
Technical Paper | doi.org/10.13182/NSE92-A23983
Articles are hosted by Taylor and Francis Online.
We show, using asymptotics, that under conditions when the angular distribution is forward peaked, the transport equation can be reduced to an advection-diffusion equation for the scalar flux. This equation describes lateral diffusive spreading with depth of an initially collimated beam of arbitrary spatial cross section and is of particular significance when scattering is highly forward peaked. Numerical results for the scalar flux for a planar source (when lateral diffusion vanishes) and in the presence of strongly anisotropic scattering are contrasted with benchmark Monte Carlo results as well as with the scalar flux obtained from a novel modified multiple scattering method. We observe that the asymptotic model is only accurate over distances small compared with the transport mean free path. It is conjectured that carrying the asymptotic expansions to higher orders or using a different asymptotic scaling might extend the accuracy of the asymptotic model to higher orders in the transport mean free path.