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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Ribbon-cutting scheduled for Advanced Manufacturing Collaborative
Energy Secretary Chris Wright will attend the opening of the Advanced Manufacturing Collaborative in Aiken, S.C., on August 7. Wright will deliver remarks and join Savannah River National Laboratory leadership and partners for a ribbon-cutting ceremony.
Robert P. Rulko, Edward W. Larsen, G. C. Pomraning
Nuclear Science and Engineering | Volume 109 | Number 1 | September 1991 | Pages 76-85
Technical Note | doi.org/10.13182/NSE91-A23845
Articles are hosted by Taylor and Francis Online.
The PN theory has been shown to be an asymptotic limit of transport theory for problems in optically thick planar-geometry media with low absorption rates and highly anisotropic scattering. Transport problems that lie outside the asymptotic regime of validity of PN theory are considered. Such problems occur in media that are either optically thin, or contain isotropic or mildly anisotropic scattering, or are not weakly absorbing. For such problems, the accuracy of numerical solutions of the PN equations obtained using the asymptotic boundary conditions is demonstrated. These numerical solutions are compared with others obtained using various familiar boundary conditions. Solutions obtained using the asymptotic boundary conditions are always competitive with, and often superior to, solutions obtained using these other boundary conditions.