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.
Parvez Salim, Yassin A. Hassan
Nuclear Technology | Volume 90 | Number 3 | June 1990 | Pages 275-285
Technical Paper | RELAP/MOD2 / Nuclear Safety | doi.org/10.13182/NT90-A34393
Articles are hosted by Taylor and Francis Online.
A best-estimate small-break loss-of-coolant accident (SBLOCA) analysis of a four-loop pressurized water reactor nuclear power plant is conducted using the computer code RELAP5/MOD2. A plant-specific RELAP5 model is developed, and steady-state operating conditions are calculated. The steady-state model is then employed to obtain SBLOCA scenarios for different break sizes. Transients resulting from the different breaks are studied to determine the limiting break size and obtain comprehensive transient scenarios. The effect of the hydraulic diameter on the transient behavior, related to the steam generator U-tubes, is also observed. The relationship between the break size and the peak cladding temperature is obtained. The study indicates that as the break size increases, a smaller core inventory instigates heatup during core boil-off.
