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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.
G. Kocamustafaogullari, S. H. Chan
Nuclear Technology | Volume 63 | Number 1 | October 1983 | Pages 23-39
Technical Paper | Nuclear Safety | doi.org/10.13182/NT83-A33300
Articles are hosted by Taylor and Francis Online.
Consideration is given to a fuel-dominated bubble, which is assumed to have just penetrated into the sodium pool in a spherical form subsequent to a hypothetical core disruptive accident. The two-phase bubble mixture is formulated as it rises through the sodium pool to the cover-gas region. The formulation takes into account the effects of the nonequilibrium mass transfer at the interfaces and of the radiative cooling of the bubble as well as the kinematic, dynamic, and thermal effects of the surrounding fields. The results of calculation for the amount of the fuel vapor condensed before the bubble reaches the cover-gas region are presented over a wide possible range of the evaporation coefficient as well as the liquid sodium-bubble interface absorbtivity. It is shown that the effects of nonequilibrium mass transfer become more meaningful at the later stage of bubble rise where the temperature difference between the liquid fuel and the gaseous mixture has been increased. The thermal radiative cooling is found to be very effective in attenuating the fuel content of the bubble; depending on the value of the liquid sodium-bubble absorbtivity, a great reduction of fuel vapor can result. Consequently, if the condensed fuel falls out of the bubble, the thermal radiation, which condenses out most of the fuel vapor, can effectively prevent and eliminate most of the fuel leakage from the reactor vessel.
