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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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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
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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.
Gabriele Grassi
Nuclear Science and Engineering | Volume 155 | Number 2 | February 2007 | Pages 208-222
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2657
Articles are hosted by Taylor and Francis Online.
A new space-angle multigrid technique has been developed to accelerate the free inner transport iterations based upon the method of characteristics (MOC). We present a two-level scheme that consists of a fine level on which the MOC transport calculation is performed and a more coarsely discretized phase-space in which a low-order problem is solved as an acceleration step. A flux-volume homogenization technique is employed to define the coarse-level cross sections. This entails the nonlinearity of the scheme. Restriction and prolongation operators are defined between the two levels. After each fine transport iteration, a low-order transport problem is iteratively solved on the homogenized grid. A coarser angular representation is used within an MOC-like framework. Discontinuity factors are employed to reconstruct the scalar incoming and outgoing currents on each region of the coarse discretization. The solution of the aforementioned low-order problem is used to correct the angular moments of the flux resulting from the previous free transport sweep. A complete description of the low-order operator and of the grid-to-grid transfer operators is given. A further application of the method to the acceleration of outer transport iterations is also presented. In order to test the effectiveness of this method, numerical tests for given benchmark geometries have been performed. Results are discussed.