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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NNSA awards BWXT $1.5B defense fuels contract
The Department of Energy’s National Nuclear Security Administration has awarded BWX Technologies a contract valued at $1.5 billion to build a Domestic Uranium Enrichment Centrifuge Experiment (DUECE) pilot plant in Tennessee in support of the administration’s efforts to build out a domestic supply of unobligated enriched uranium for defense-related nuclear fuel.
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.