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
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
Dec 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
January 2026
Nuclear Technology
December 2025
Fusion Science and Technology
November 2025
Latest News
Blades-in turbine inspections at Quad Cities set new benchmark for Constellation
When Constellation decided to install replacement Alstom low-pressure turbines at three of its boiling water reactor plants more than 15 years ago, one benefit was knowing the new turbines should operate reliably—and without major inspections—for several years.
S. Van Criekingen, E. E. Lewis, R. Beauwens
Nuclear Science and Engineering | Volume 152 | Number 2 | February 2006 | Pages 149-163
Technical Paper | doi.org/10.13182/NSE06-1
Articles are hosted by Taylor and Francis Online.
A mixed-hybrid treatment of the spatial variables of the within-group neutron transport equation generalizes existing mixed and hybrid methods, combining their attractive features: the simultaneous approximation of even- and odd-parity angular flux components and the use of Lagrange multipliers to enforce interface continuity. A finite element spatial discretization and spherical harmonic angular expansions are used. We discuss rank conditions for the proposed methods and provide a new derivation of the Rumyantsev interface conditions. Even- and odd-parity interface continuity properties corresponding to these Rumyantsev conditions are established. We examine inclusion conditions and the interaction of the primal/dual distinction due to the spatial variable with the even/odd-order spherical harmonic approximation distinction due to the angular variable. Numerical solutions for both even- and odd-order spherical harmonic approximations are presented, and a promising enclosing property is observed in our results.