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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
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.
Gad Shani
Nuclear Science and Engineering | Volume 52 | Number 2 | October 1973 | Pages 215-226
Technical Paper | doi.org/10.13182/NSE73-A28191
Articles are hosted by Taylor and Francis Online.
Neutron waves in a reflected reactor are analyzed using the two-group diffusion equation. The solution is composed of a transient which disappears within a few milliseconds, a steady-state part, and an oscillatory part. The last is comprised of four terms corresponding to four waves: two propagating waves and two reflected waves. When a sinusoidal source of thermal neutrons is applied to a water-moderated multiplying medium, the source wave amplitude decays with a relaxation length equal to the diffusion length of the medium. A wave of fast neutrons is then produced by fission which is induced by the source wave. This fast-neutron wave carries the wave phenomenon across the core. The two propagating thermal-neutron waves are (a) the source wave, and (b) a wave of thermalized fission neutrons. The two reflected waves are the reflections of the two propagating waves. The amplitudes and phases of the four waves are calculated, together with those of the total wave which is the sum of the four partial waves. The agreement of the measured data of the total wave with the calculations is reasonable. Modulated poison and source oscillators were used for the experiments. The reactor response to both was essentially the same except in the region near the oscillators; while the first decreased the number of neutrons, the second increased their number.