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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 96 | Number 3 | July 1987 | Pages 234-240
Technical Note | doi.org/10.13182/NSE87-A16384
Articles are hosted by Taylor and Francis Online.
The one-speed transport equation is solved for a ring reactor. A complete solution is obtained for the space-time relaxation of a pulse of neutrons in a multiplying medium in which delayed neutrons are neglected. The solution consists of a fundamental mode, a finite number of harmonics, and an integral transient. A condition is deduced, which gives the maximum number of harmonics that can exist for a given ring circumference. The limitations of diffusion theory are pointed out with particular reference to the shortcomings of that theory in dealing with the early stages of evolution of the pulse. Delayed neutrons are included and a complete solution is obtained by means of the prompt jump approximation. The results are illustrated by numerical calculations designed to show the onset of instabilities in the harmonics when the reactor is sufficiently large.