ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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!
Latest Magazine Issues
Aug 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
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.
Ronald Mattis, Alireza Haghighat
Nuclear Science and Engineering | Volume 111 | Number 2 | June 1992 | Pages 180-196
Technical Paper | doi.org/10.13182/NSE92-A23932
Articles are hosted by Taylor and Francis Online.
Several vector and parallel processing algorithms for the inherently recursive Sn method are developed for two-dimensional curvilinear geometries. The iterative sweeps through the spatial and directional meshes are decomposed into various independent subdomains suitable for multiprocessing on shared memory architectures. Both spatial decomposition (using both axial and radial groups) and angular decomposition (using directional groups) are used. The new algorithms are implemented on the six-processor Cornell National Supercomputing Facility IBM 3090/600J computer using the IBM parallel Fortran compiler. The algorithm behaviors are investigated using a series of r-z cylindrical geometry fixed-source problems. In addition, to verify the algorithm performance for realistic problems, a two-group, r-θ geometry, pressurized water reactor (PWR) source calculation is performed. Total speedups as high as 5.86 are observed for the PWR model compared with the one-processor solution. The suitability of these algorithms for highly parallel architectures is also discussed.