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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.
Nikolay Ivanov Kolev
Nuclear Technology | Volume 83 | Number 1 | October 1988 | Pages 65-80
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34176
Articles are hosted by Taylor and Francis Online.
High-pressure gas injection into a low-pressure liquid pool with a free surface in cylindrical geometry with internals was numerically simulated using the computer code IVA2/005. Bubble formation and pressure history as a function of time were predicted and compared with the experimental observation for a 0.6-MPa pressure source. A comparison with the previous prediction of a 1.1-MPa pressure source experiment is made. Numerical diffusion and flow pattern prediction influence the gas propagation, which influences in turn the sharpness of the predicted bubble and water surface and the pressure history in time. The same geometry, but with a gas, was computationally simulated. The comparison proves that the code integrator works well without a constitutive package. Methods to measure the reduction of numerical diffusion are proposed. Comparison with the tree acoustic experiments shows that IVA2 can simulate pressure wave phenomena in two-phase two-component mixtures with strong nonhomogeneity.
