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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
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 155 | Number 1 | January 2007 | Pages 109-118
Technical Note | doi.org/10.13182/NSE05-73TN
Articles are hosted by Taylor and Francis Online.
The polynomial chaos functions of Wiener are used to solve a stochastic differential equation. It is shown that a variety of polynomials are available according to the probability distribution of the underlying random element. Using the Legendre chaos polynomials, we have solved the problem of radiation transmission through a slab of random material properties in the P1 approximation. For a special case, it is possible to obtain an exact solution to this problem, and hence the rate of convergence of the chaos expansion can be examined. Results are shown in tabular form and graphically, which compare the stochastic average with the deterministic average and significant differences are found. In addition we calculate the variance in the flux and current across the slab, thereby giving a measure of the uncertainty associated with the average. The method of polynomial chaos offers an alternative procedure to the normally used closure, or special statistics, methods for the study of spatial randomness and has the potential to deal with very complex systems, although the full computational implications have yet to be determined. In the Appendix, we show how the Boltzmann equation, with spatially random cross sections, can be reduced to a coupled set of deterministic equations.