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.
Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting 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
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
July 2025
Fusion Science and Technology
Latest News
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Ricardo C. De Barros, Edward W. Larsen
Nuclear Science and Engineering | Volume 111 | Number 1 | May 1992 | Pages 34-45
Technical Paper | doi.org/10.13182/NSE92-A23921
Articles are hosted by Taylor and Francis Online.
A new nodal method is developed for the solution of one-group discrete ordinates (SN) problems with linearly anisotropic scattering in x,y-geometry. In this method, the “spectral Green’s function” (SGF) scheme, originally developed for solving SN problems in slab geometry with no spatial truncation error, is generalized to solve the one-dimensional transverse-integrated SN nodal equations with the “constant” approximation for the transverse leakage terms. The resulting “SGF-constant nodal” (SGF-CN) method is more accurate than conventional coarse-mesh methods for deep penetration problems because it treats the scattering source terms implicitly and exactly; the only approximation involves the transverse leakage terms. In conventional SN nodal methods, the transverse leakage terms and scattering source are both approximated. We solve the SGF-CN equations using the one-node block inversion iterative scheme, which uses the best available estimates for the node-entering fluxes to evaluate the node-exiting fluxes in the directions that constitute the incoming fluxes for the adjacent nodes as the equations are swept across the system. Finally, we give numerical results that illustrate the accuracy of the SGF-CN method for coarse-mesh calculations.