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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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!
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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.
Kirk Mathews, James Dishaw, Nicholas Wager, Nicholas Prins
Nuclear Science and Engineering | Volume 163 | Number 3 | November 2009 | Pages 191-214
Technical Paper | doi.org/10.13182/NSE163-191
Articles are hosted by Taylor and Francis Online.
Our partial-current-transport (PCT) approach uses the partial currents through the faces of cells in a spatial grid as the unknowns in a linear algebra problem. Emission and externally incident currents are the knowns. The coefficient matrix is determined by boundary conditions and transport within cells. Adaptive PCT models include within-cell flux-distribution parameters that are found by distribution iteration (DI). Upon convergence, scalar fluxes are computed. We develop the approach in general and derive (in slab geometry) a fixed-coefficient PCT diffusion method and an adaptive PCT discrete ordinates method. A parallelized direct solver is used for the large but very sparse linear algebra problem that couples all the cells. Matrix inversion is used for the dense but small within-cell problems. These direct solvers eliminate scattering source iteration (SI). Though requiring more storage, much or most of the computational effort is pleasingly parallel, making the method attractive for large parallel machines with large memories. In comparing our slab geometry implementation with PARTISN, we observed that DI used as many or fewer iterations than SI and succeeded where SI failed, whether alone or with diffusion synthetic acceleration or transport synthetic acceleration. We conclude that DI for adaptive PCT holds great promise as an alternative to SI and its accelerators.