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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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.
Yunzhao Li, Zhipeng Li, Hongchun Wu, Youqi Zheng
Nuclear Science and Engineering | Volume 190 | Number 2 | May 2018 | Pages 134-155
Technical Paper | doi.org/10.1080/00295639.2017.1417346
Articles are hosted by Taylor and Francis Online.
To reduce the calculation effort and memory requirement for high-order PN expansion calculation in the Variational Nodal Method (VNM), the surficial irreducible basis functions based on the symmetry group theory have been employed to block-diagonalize one of the four nodal response matrices. Its effectiveness encourages our further investigation on the application of the symmetry group theory to volumetric expansion to block-diagonalize the remaining three of the nodal response matrices in this paper. By using the symmetry group theory, the neutron transport problem for each node can be decoupled into several independent subproblems as long as both the geometry and the material distribution of the node are symmetric. Each of these subproblems can be solved by using variational principles as in the traditional VNM, providing their nodal response matrices as the diagonal blocks of the corresponding entire ones. For hexagonal-z node, each nodal response matrix can be reduced into 16 diagonal blocks, among which only 12 have to be calculated due to the properly selected irreducible basis functions. In addition, it is also proved that the response matrices with anisotropic scattering can also be block-diagonalized as the same. Calculation results based on typical problems demonstrate that the new method reduces the time cost for the response matrice calculation by one order of magnitude compared with our previous work. For the total computing time, the speedup ratio is about 2 for P3 calculation and 4 for P5 calculation. Furthermore, almost 40% of the memory requirement can be saved.