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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 Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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Latest News
EPA issues final rule regulating “forever chemicals”
The Environmental Protection Agency announced that it will issue a rule aimed at limiting public exposure to per- and polyfluoroalkyl substances (PFAS). The final rule will designate two widely used PFAS chemicals, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also known as Superfund.
According to the EPA, both PFOA and PFOS meet the statutory criteria for designation as hazardous substances.
Avner P. Cohen, Roy Perry, Shay I. Heizler
Nuclear Science and Engineering | Volume 192 | Number 2 | November 2018 | Pages 189-207
Technical Paper | doi.org/10.1080/00295639.2018.1499339
Articles are hosted by Taylor and Francis Online.
Modeling the propagation of radiative heat waves in optically thick material using a diffusive approximation is a well-known problem. In optically thin material, classic methods, such as classic diffusion or classic , yield the wrong heat wave propagation behavior, and higher-order approximation might be required, making the solution more difficult to obtain. The asymptotic approximation [Heizler, Nucl. Sci. Eng., Vol. 166, p. 17 (2010)] yields the correct particle velocity but fails to model the correct behavior in highly anisotropic media, such as problems that involve a sharp boundary between media or strong sources. However, the solution for the two-region Milne problem of two adjacent half-spaces divided by a sharp boundary yields a discontinuity in the asymptotic solutions that makes it possible to solve steady-state problems, especially in neutronics. In this work we expand the time-dependent asymptotic approximation to a highly anisotropic medium using the discontinuity jump conditions of the energy density, yielding a modified discontinuous equation in general geometry. We introduce numerical solutions for two fundamental benchmarks in plane symmetry. The results thus obtained are more accurate than those attained by other methods, such as Flux Limiters or Variable Eddington Factors.