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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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August 2024
Latest News
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.
K. D. Lathrop, N. S. Demuth
Nuclear Science and Engineering | Volume 32 | Number 1 | April 1968 | Pages 120-130
Technical Paper | doi.org/10.13182/NSE68-A18831
Articles are hosted by Taylor and Francis Online.
A new system of biorthogonal polynomials is developed for the angular expansion of the directional flux in the linear Boltzmann transport equation. It is shown in systems infinite in one space dimension that the angular integral in the Boltzmann equation can be reduced to a weighted integral over the unit circle. The corresponding system of orthogonal functions is found to be a system of two sets of polynomials in two variables. Recursion relations and an addition theorem are derived for these polynomials. The angular dependence of the particle flux is expanded in each set of these polynomials. Systems of partial differential equations are derived for the expansion coefficients, that is, for angular moments of the particle flux. One of these systems is shown to be a specific linear combination of the equations obtained when the directional flux is expanded in spherical harmonics functions specialized for the geometry considered. It is shown that this same system, in (x, y) geometry, reduces simply to the spherical harmonics equations in one-dimensional plane geometry.