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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
Vincent P. Manno, Michael W. Golay
Nuclear Technology | Volume 70 | Number 1 | July 1985 | Pages 124-132
Technical Paper | Third International Retran Meeting / Nuclear Safety | doi.org/10.13182/NT85-A33671
Articles are hosted by Taylor and Francis Online.
The LIMIT computer code is utilized to study the behavior of containment atmospheres following severe core damage accidents. The degree of heterogeneity in passive entity mixing, especially mass stratification, is assessed. Two scenarios are analyzed using a two-dimensional Cartesian 84-node mesh computational domain as the baseline geometry. Both calculations include steam and liquid fields and involve hydrogen injection. Some stratification is observed after source injections are terminated. The formation of the stable mass gradients is caused principally by heat removal to structures located in the lower regions. Preliminary results conclude that in the absence of sprays or fan coolers, stratification can occur depending on the location and heat capacity of energy absorbing/liberating structures.
