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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.
Yoshio Murao, Tsuneyuki Hojo
Nuclear Technology | Volume 80 | Number 1 | January 1988 | Pages 83-92
Technical Paper | Advanced Light Water Reactor / Fission Reactor | doi.org/10.13182/NT88-A35551
Articles are hosted by Taylor and Francis Online.
To evaluate the applicability of the reflood analysis code REFLA for ordinal pressurized water reactors to the analysis of reflooding phenomena in light water high conversion reactors (LWHCRs) with tight-lattice cores, a numerical simulation of the NEPTUN LWHCR test was performed with the REFLA code. The NEPTUN LWHCR test was performed at the Swiss Federal Institute for Reactor Research with a test section simulating the tight-lattice core of an LWHCR. The results indicate no potential problems in the use of REFLA for the simulation of reflooding behavior in tight-lattice rod bundles. To improve the code, however, it is recommended to modify models of core heat transfer at a high flooding rate and core water distribution (integration of droplet flow) in the axial direction, and to investigate core pressure drop and horizontal cross flow.
