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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
H. Brockmann
Nuclear Science and Engineering | Volume 132 | Number 1 | May 1999 | Pages 127-134
Technical Note | doi.org/10.13182/NSE99-A2054
Articles are hosted by Taylor and Francis Online.
In calculating neutral particle transport through elongated voids with the discrete ordinates method, the problem of ray effect may occur if standard angular quadrature sets are used. To mitigate this ray effect, the configuration-factor concept developed in the theory of thermal radiation for calculating the radiation exchange among surfaces is applied here. The common configuration-factor concept is extended in such a way that the angular dependence of the radiation emitted from the surfaces can be considered. The method is applied to regular and annular cylinders with r-z geometry and incorporated into a two-dimensional discrete ordinates transport code. Calculations on a narrow-duct-streaming problem show that the ray effect is strongly reduced by this method. The new method gives results equivalent to or even better than a standard discrete ordinates calculation using a biased angular quadrature set with 166 directions at computing times for one inner iteration that are about a factor of 2 less.