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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.
Alireza Haghighat
Nuclear Science and Engineering | Volume 108 | Number 3 | July 1991 | Pages 267-277
Technical Paper | doi.org/10.13182/NSE91-A23824
Articles are hosted by Taylor and Francis Online.
A parallel algorithm for angular domain decomposition (or parallelization) of an r-depen-dent spherical Sn transport theory method is derived. The parallel formulation is incorporated into TWOTRAN-II using the IBM Parallel FORTRAN compiler and implemented on an IBM 3090/400 (with four processors). The behavior of the parallel algorithm for different physical problems is studied, and it is concluded that the parallel algorithm behaves differently in the presence of a fission source as opposed to the absence of a fission source; this is attributed to the relative contributions of the source and the angular redistribution terms in the Sn algorithm. Further, the parallel performance of the algorithm is measured for various problem sizes and different combinations of angular subdomains or processors. Poor parallel efficiencies between ∼ 35 and 50% are achieved in situations where the relative difference of parallel to serial iterations is ∼ 50%. High parallel efficiencies between ∼ 60% and 90% are obtained in situations where the relative difference of parallel to serial iterations is <35%.
