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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
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.
Mario Dalle Donne, Walter Hame
Nuclear Technology | Volume 71 | Number 1 | October 1985 | Pages 111-124
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A33713
Articles are hosted by Taylor and Francis Online.
Many critical heat flux (CHF) correlations have been developed for water-cooled rod clusters representing typical pressurized water reactor (PWR) or boiling water reactor fuel element geometries with relatively wide rod lattices. The fuel elements of an advanced pressurized water reactor (APWR), however, have a tight fuel rod lattice in order to increase fuel utilization. It was therefore decided to produce a new CHF correlation valid for rod bundles with tight lattices. The already available WSC-2 correlation was chosen as a basis. The geometry-dependent parameters of this correlation were again determined by root-mean-square fitting from the experimental data of CHF test performed within the framework of the light water breeder reactor program at Bettis Atomic Power Laboratory. These tests include triangular arrays of rod bundles with very tight lattices. The effects of spiral spacer ribs were based on experimental data from Columbia University. The present correlation was compared with various tests performed with rod bundles with wire wrapped spacers. Application of the new CHF correlation to conditions typical for an APWR shows that the predicted CHFs are smaller than those calculated with the usual PWR CHF correlations.
