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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Leading the charge: INL’s role in advancing HALEU production
Idaho National Laboratory is playing a key role in helping the U.S. Department of Energy meet near-term needs by recovering HALEU from federal inventories, providing critical support to help lay the foundation for a future commercial HALEU supply chain. INL also supports coordination of broader DOE efforts, from material recovery at the Savannah River Site in South Carolina to commercial enrichment initiatives.
Mustafa Alper Yildiz, Elia Merzari, Thien Nguyen, Yassin A. Hassan
Nuclear Technology | Volume 208 | Number 8 | August 2022 | Pages 1279-1289
Technical Paper | doi.org/10.1080/00295450.2022.2049964
Articles are hosted by Taylor and Francis Online.
This paper presents a direct numerical simulation (DNS) and proper orthogonal decomposition (POD) of the flow in a randomly packed pebble bed. Nek5000, a spectral-element computational fluid dynamics code, was used to develop the DNS fluid flow data, including first- and second-order statistics for an experimental randomly packed pebble bed. Turbulence budgets were also produced.
The flow domain consists of 147 pebbles enclosed by a bounding wall. In the present work, the Reynolds number is 1700 based on the hydraulic diameter and interstitial velocity. First- and second-order statistics were compared with the experimental data. The POD analysis was performed to identify dominant flow structures, especially in the wall channeling region.