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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.
Toshiya Takaki, Michio Murase, Kosuke Hayashi, Akio Tomiyama
Nuclear Technology | Volume 208 | Number 3 | March 2022 | Pages 503-519
Technical Paper | doi.org/10.1080/00295450.2021.1927616
Articles are hosted by Taylor and Francis Online.
The objective of this study was to reduce the uncertainties of correlations for flow characteristics in vertical pipes under flooding at the top end. The void fraction α, pressure gradient dP/dz, and countercurrent flow limitation (CCFL) were previously measured with diameter D = 40 mm and working fluid of air and water. The wall friction and interfacial friction factors (fw and fi) were obtained based on the annular flow model, and CCFL and fw were evaluated in detail. Hence, attention was turned to detailed evaluations of α and fi. Liquid film thickness δ and interfacial friction factor fi for smooth film (SF) due to flooding at the top end were obtained using the previously derived fw correlation and existing dP/dz data with D = 20 to 50.8 mm and pressure P = 0.1 to 4.1 MPa, and empirical correlations for δ and fi were derived. The δ term was well expressed by a function of the liquid Reynolds number ReL, and the uncertainty of the δ correlation was ±0.0062 for α = 0.87 to 0.98. fi was expressed by a function of δ/L (where L is the Laplace length) or the Kutateladze parameter KG*, the dimensionless diameter D* (=D/L), and the density ratio of the gas and liquid phases ρG/ρL. The applicability of the derived correlations to conditions of D = 300 mm and P = 7 MPa was evaluated, and the fi correlation was modified based on fi values computed with the δ correlation. The drift-flux parameters for SF were also considered.
