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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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.
Charlotte Sandrin, Richard Sanchez, Florence Dolci
Nuclear Science and Engineering | Volume 168 | Number 1 | May 2011 | Pages 59-72
Technical Paper | doi.org/10.13182/NSE10-44
Articles are hosted by Taylor and Francis Online.
Today's reactor core calculations are done in diffusion with a few coarse groups and require the homogenization of the core assemblies as well as a correct representation of the reflector. In industrial applications a homogeneous reflector is often used with cross sections obtained from transport calculations and adjusted to fit in-core measurements. However, the need for better precision in the core diffusion calculations and the emergence of new reflector concepts, such as for the European Pressurized Reactor (EPR), require an increase in the number of coarse groups for novel loading patterns and a rethinking of how to define the equivalent reflector. In this work we analyze and extend current techniques for the reflector homogenization for core calculations. Following the adopted industrial methodology, we have perfected a technique for the determination of an equivalent homogenous reflector by implementing a Particle Swarm Optimization Algorithm and showed its limitations through the analysis of an academic slab reactor model and of a realistic two-dimensional representation of the EPR. We have compared the precision of the resulting core calculations to transport reference calculations as well as to diffusion calculations using a multigroup albedo boundary condition. We have also explored the use of current-preserving flux discontinuity coefficients at the core-reflector interface in conjunction with an equivalent reflector.