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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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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.
A. N. Verma, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 745-750
Technical Note | doi.org/10.13182/NSE77-A15217
Articles are hosted by Taylor and Francis Online.
Using the flux synthesis method and energy -dependent boundary conditions, we have solved the three-dimensional multigroup diffusion equation, without as suming space-energy separability and without explicitly introducing the concept of buckling, to study the diffusion of neutrons inside beryllium assemblies with finite transverse dimensions. The energy -dependent neutron spectra have been reported at various distances inside the two experimental assemblies of Lake and Kallfelz (35.6 × 35.6 × 50.8 cm3 and 25.4 × 25.4 × 50.8 cm3). We have discussed in detail the problem of the existence of a true discrete or a pseudo-asymptotic mode in these assemblies. We have also defined an “equivalent buckling” and find that the equivalent buckling agrees with the conventional definition of buckling only in large assemblies and only then in the epicold energy region. We have also discussed the validity of using diffusion theory in small assemblies.