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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Nuclear News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
To hear more insights from this talented group of young professionals, watch the “40 Under 40 Roundtable: Perspectives from Nuclear’s Rising Stars” on the ANS website.
J. I. Duo, Y. Y. Azmy
Nuclear Science and Engineering | Volume 156 | Number 2 | June 2007 | Pages 139-153
Technical Paper | doi.org/10.13182/NSE05-91
Articles are hosted by Taylor and Francis Online.
Error norms for three variants of Larsen's benchmark problem are evaluated using three numerical methods for solving the discrete ordinates approximation of the neutron transport equation in multidimensional Cartesian geometry. The three variants of Larsen's test problem are concerned with the incoming flux boundary conditions: unit incoming flux on the left and bottom edges (Larsen's configuration); unit incoming flux only on the left edge; unit incoming flux only on the bottom edge. The three methods considered are the diamond-difference (DD) method, the arbitrarily high order transport (AHOT) method of the nodal type (AHOT-N), and of the characteristic type (AHOT-C). The last two methods are employed in constant, linear, and quadratic orders of spatial approximation. The cell-wise error is computed as the difference between the cell-averaged flux computed by each method and the exact value, then the L1, L2, and L error norms are calculated. The new result of this study is that while integral error norms, i.e., L1 and L2, converge to zero with mesh refinement, the cellwise L norm does not. Via numerical experiments we relate this behavior to solution discontinuity across the singular characteristic. Little difference is observed between the error norm behavior of the methods in spite of the fact that AHOT-C is locally exact, suggesting that numerical diffusion across the singular characteristic is the major source of error on the global scale. Nevertheless, increasing the order of spatial approximation in AHOT methods yields higher accuracy in the integral error norms sense. In general, the characteristic methods possess a given accuracy in a larger fraction of the number of computational cells compared to nodal methods or DD.