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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.
Christoph Homann, Maurizio Bottoni, Burkhardt Dorr, Dankward Struwe
Nuclear Technology | Volume 91 | Number 3 | September 1990 | Pages 275-286
Technical Paper | Fission Reactor | doi.org/10.13182/NT90-A34452
Articles are hosted by Taylor and Francis Online.
The computer code BACCHUS has been developed for thermal-hydraulic calculations of coolant flows in reactor geometries with hexagonal pin arrangements. It has been used in its two-dimensional single-phase version for the interpretation of the first three experiments of the in-pile series Mol 7C in a sodium-cooled 37-pin bundle. The modeling of experimental details is described. Results for the coolant flow and temperature distributions in the blocked region are presented for selected Mol 7C cases for steady-state and transient conditions up to boiling inception. The extrapolation of the results to reactor conditions is done in several steps. First, the features that are specific for the Mol 7C experiments are removed, and then the bundle is enlarged to a size typical for reactors.
