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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
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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.
Pierre Benoist
Nuclear Science and Engineering | Volume 77 | Number 1 | January 1981 | Pages 1-12
Technical Paper | doi.org/10.13182/NSE81-A21334
Articles are hosted by Taylor and Francis Online.
In an earlier work, the author presented a theory of the diffusion coefficient in a reactor lattice, leading to expressions valid in full generality. However, for practical purposes it was necessary to admit simplifying assumptions. But now, with the help of modern computers, weaker approximations appear possible. Assuming only two hypotheses, (a) zero-order approximation in , and (b) cylindricalization of the cell, a diffusion coefficient calculation can be transformed into a one-dimensional problem, the solution of which is practically as simple as the calculation of the classical fine structure. The difficulty concerning the reflection of neutrons from the boundary is overcome here; moreover, handling of angular fluxes is avoided, without any approximation. Formulas for the calculation of the diffusion coefficients in the framework of integral transport theory are presented.