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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Senate EPW Committee to hold Nieh nomination hearing
Nieh
The Senate Environment and Public Works Committee will hold a nomination hearing Wednesday for Ho Nieh, President Donald Trump’s nominee to serve as commission at the Nuclear Regulatory Commission.
Trump nominated Nieh on July 30 to serve as NRC commissioner the remainder of a term that will expire June 30, 2029, as Nuclear NewsWire previously reported.
Nieh has been vice president of regulatory affairs at Southern Nuclear since 2021, though since June 2024 he has been at the Institute of Nuclear Power Operations as a loaned executive.
A return to the NRC: If confirmed by the Senate, Nieh would be returning to the NRC after three previous stints totaling nearly 20 years.
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.