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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Ho Nieh nominated to the NRC
Nieh
President Trump recently nominated Ho Nieh for the role of commissioner in the Nuclear Regulatory Commission through the remainder of a term that will expire June 30, 2029.
Nieh has been the vice president of regulatory affairs at Southern Nuclear since 2021, though he is currently working as a loaned executive at the Institute of Nuclear Power Operations, where he has been for more than a year.
Nieh’s experience: Nieh started his career at the Knolls Atomic Power Laboratory, where he worked primarily as a nuclear plant engineer and contributed as a civilian instructor in the U.S. Navy’s Nuclear Power Program.
From there, he joined the NRC in 1997 as a project engineer. In more than 19 years of service at the organization, he served in a variety of key leadership roles, including division director of Reactor Projects, division director of Inspection and Regional Support, and director of the Office of Nuclear Reactor Regulation.
B. S. Pei, Y. B. Chen, Chunkuan Shih, W. S. Lin
Nuclear Technology | Volume 75 | Number 2 | November 1986 | Pages 134-147
Technical Paper | Fission Reactor | doi.org/10.13182/NT86-A33856
Articles are hosted by Taylor and Francis Online.
The performance of five critical heat flux (CHF) correlations with the COBRA IIIC/MIT-1 code was evaluated. These correlations were evaluated against a data group comprised of 2943 axial nonuniform, rod bundle, first-order, and higher rank CHF data points of pressurized water reactor (PWR) core geometries. Among these five CHF correlations, EPRI-1 is the most accurate and has the widest operating ranges. Two kinds of correction factors—cold-wall correction factors and the CHF local quality correction factor—were developed and introduced to EPRI-1 to improve its accuracy in PWR CHF predictions. An in-depth evaluation of the EPRI-1 correlation in the prediction of CHFs of three fuel element abnormalities was also performed. Heat flux spikes and blocked channel conditions have negligible effects on CHFs. For the adverse effects of rod bowing on CHFs, the severity of rod bowing effects depends on the percentage of gap closure between rods, and also on the presence of any thimble tube (cold wall) adjacent to the distorted subchannel. Rod bowing effect parameter correlations under cold-wall conditions were developed. These rod bowing effect parameter correlations were tested; it was proved that they could closely describe the rod bowing effects with no apparent remaining residual trends.
