ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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!
Latest Magazine Issues
Aug 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
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.
M. Ishii, W. L. Chen, M. A. Grolmes
Nuclear Science and Engineering | Volume 69 | Number 2 | February 1979 | Pages 297-318
Technical Paper | doi.org/10.13182/NSE79-2
Articles are hosted by Taylor and Francis Online.
During an unprotected undercooling accident in a liquid-metal fast breeder reactor, the motion and relocation of the molten fuel cladding can be important because of their potentially significant effect on reactivity, blockage formation, and subsequent fuel motion. The present study analyzes the cladding relocation problem based on a multichannel film flow model. The important aspects considered in the analysis are the nonuniform transverse cladding melting pattern and sodium vapor flow diversions within a subassembly. It has been shown that the motion of molten fuel cladding and subsequent blockage formations can be significantly influenced by this interconnected channel effect. Several sample calculations have been made to demonstrate these points.