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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.
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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
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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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.
Wang Kee In
Nuclear Technology | Volume 134 | Number 2 | May 2001 | Pages 187-195
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT01-1
Articles are hosted by Taylor and Francis Online.
A numerical study was conducted to investigate the nuclear fuel assembly coolant flow mixing that is promoted by the flow deflectors on the grid spacer. Four typical flow deflectors (split vane, side-supported vane, swirl vane, and twisted vane) were chosen for this study. A single subchannel of one grid span is modeled using the flow symmetry. The predicted axial and lateral mean flow velocities, and the turbulent kinetic energy in the subchannel for the split-vane design, are in good agreement with the experimental results.The split vane and the twisted vane generate a large cross flow between the subchannels and a skewed elliptic swirling flow in the subchannel near the grid spacer. The cross flow rapidly decreases and the swirling flow becomes dominant downstream of the spacer. The side-supported vane induces a horizontally elongated elliptic swirl in the subchannel and a secondary flow in the near downstream of the spacer. The swirl vane produces a circular swirling flow in the subchannel and a negligible cross flow. For the twisted-vane and side-supported vane designs, the change in direction of the cross flow was predicted. The average turbulent kinetic energy in the subchannel sharply increases near the spacer and rapidly decreases to a fully developed level. In summary, the numerical results showed a somewhat large difference from the experimental results near the spacer but represented the overall characteristics of coolant mixing well in a nuclear fuel bundle with the flow deflectors on the grid spacer.