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
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Richard Sanchez, Li Mao, Simone Santandrea
Nuclear Science and Engineering | Volume 140 | Number 1 | January 2002 | Pages 23-50
Technical Paper | doi.org/10.13182/NSE140-23
Articles are hosted by Taylor and Francis Online.
Boundary conditions are an essential part of the approximations used in the numerical solution of the transport equation. The collision probability and the characteristic methods are considered, and exact and approximated tracking methods to be used in the implementation of geometrical motions and albedo conditions are analyzed. The analysis of the exact boundary-condition treatment is carried out for finite domains and infinite lattices, where periodic trajectories must be used. Albedo-like boundary conditions may be used to approximate exact geometrical motions via spatially piecewise constant and either piecewise constant or discrete angular approximations for the boundary fluxes. We also have examined angular product quadrature formulas and shown that the recently proposed Bickley-Naylor quadratures do not respect particle conservation in the presence of anisotropy of scattering. Numerical examples show that the approximated albedo-type boundary method converges toward the results obtained with the exact boundary treatment. However, because of problems related to the multigroup implementation, numerical extra burden in group iterations prevents the efficient use of approximated boundary conditions for multigroup calculations. Nevertheless, this method remains a candidate of choice for use in multidomain calculations via interface boundary fluxes.