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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.
Min Seop Song, Eung Soo Kim (Seoul Natl Univ), Jae Ho Jeong (KAERI)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 531-546
The wire-wrapped pin bundle is the most commonly adopted form of the fuel assembly in SFRs. It is challenging to measure the local flow velocity field experimentally because of its narrow channel and complex internal shape. In this study, the refractive indices of the fluid and the test-section are matched and the flow field in the SFR wire-wrapped 19-pin bundle is visualized using optical measurement techniques such as PIV/LDV and compared with the RANS-based computational fluid dynamic (CFD) analysis. According to the turbulence intensity and the pressure drop measurements, it is observed that the flow regime changes from the transition regime to the fully turbulent regime when the Re number is more than 13,000. In addition, the pressure drop measurement results are compared with the CFD analysis for various turbulence models, and it is found that the BSL-RSM model predicts the experimental results the most accurately. The velocity distribution obtained in the edge sub-channel using PIV is also compared with the CFD results. As a result, the flow and vortex shapes are very similar to each other qualitatively. However, some discrepancies are observed quantitatively in the region where the channel thickness is narrow. The main reason is considered to be attributed to the pin location error, the refraction of light and the velocity averaging due to the thickness of the laser sheet incident on the thin channel during the experiment. Further investigation is on-going for analysis of flow in interior subchannel.