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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
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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.
S. Yamashita
Nuclear Science and Engineering | Volume 54 | Number 4 | August 1974 | Pages 432-444
Technical Paper | doi.org/10.13182/NSE74-A23437
Articles are hosted by Taylor and Francis Online.
Accurate kinetics equations, which can be applied to a square and to a two-step gas-separation cascade composed of stages with a large separation factor, are derived from the exact conservation of matter in the unsteady state. The derivation is based on the assumptions that flow rates and holdups are independent of time and that the second derivative of the assay with respect to time can be neglected. If two or three additional assumptions, including the important one that the separation factor is nearly equal to unity, are added to those above, the author’s equations reduce to Cohen’s kinetics equations. If a square cascade with eight stages composed of separators having a separation factor of 1.1 is supposed to be operated in total reflux, the results of the calculations disclose that the assays and the 98% equilibrium times obtained from the conventional equations are overestimated by ∼12 and ∼10%, respectively, compared with those obtained from the author’s equations. The author’s kinetics equations promise to be useful for analyzing the kinetics of a square cascade with a large separation factor such as a centrifuge.