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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.
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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.
M. M. R. Williams
Nuclear Science and Engineering | Volume 173 | Number 2 | February 2013 | Pages 182-196
Technical Note | doi.org/10.13182/NSE12-11
Articles are hosted by Taylor and Francis Online.
A method has been developed that provides analytic solutions for two-dimensional cell problems for the neutron transport equation. This is made possible by assuming an infinite, repeating lattice of rectangular regions. The solution is effected by means of a finite Fourier transform, the periodicity of which is related to the size of the unit cell. In order to drive the flux, we assume that the cell is composed of two regions: an inner circular region and the remaining exterior part. Different sources are placed in each region thereby leading to a situation rather like the conventional reactor cell problem but with no spatial variation of the cross sections. The method is illustrated by two examples: the Levermore-Pomraning equations and the two-group equations. In the former case, we have obtained the stochastically averaged flux within the cell and also the Pomraning χ-function. In addition, we have calculated the ratio of the spatially averaged flux in the outer region to that in the inner circular region, i.e., the disadvantage factor. Fluxes and disadvantage factors are also obtained for the two-group equations, and the rate of convergence is shown. These results are exact transport theory solutions and are offered as benchmarks for checking transport theory codes. The calculations are also repeated using diffusion theory. The SPN method, which we show to be exact for our problem, is used to demonstrate the rate of convergence of the PN method for two-dimensional cell problems.