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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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!
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Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Jongtae Kim, Seong-Wan Hong, Sang-Baik Kim, Hee-Dong Kim
Nuclear Technology | Volume 150 | Number 3 | June 2005 | Pages 263-282
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT05-A3621
Articles are hosted by Taylor and Francis Online.
In order to analyze the hydrogen distribution during a hypothetical station blackout accident in the Korean next-generation Advanced Power Reactor 1400 (APR1400) containment, the three-dimensional computational fluid dynamics code GASFLOW was used. The source of the hydrogen and steam for the GASFLOW analysis was obtained from a MAAP calculation. The discharged water, steam, and hydrogen from the pressurizer are released into the water of the in-containment refueling water storage tank (IRWST). Most of the discharged steam is condensed in the IRWST water because of its subcooling, and dry hydrogen is released into the free volume of the IRWST; finally, it goes out to the annular compartment above the IRWST through the vent holes. From the GASFLOW analysis, it was found that the gas mixture in the IRWST becomes quickly nonflammable by oxygen starvation but the hydrogen is accumulated in the annular compartment because of the narrow ventilation gap between the operating deck and containment wall when the igniters installed in the IRWST are not operated. When the igniters installed in the APR1400 were turned on, a short period of burning occurred in the IRWST, and then the flame was extinguished by the oxygen starvation in the IRWST. The unburned hydrogen was released into the annular compartment and went up to the dome because no igniters are installed around the annular compartment in the base design of the APR1400. From this result, it could be concluded that the control of the hydrogen concentration is difficult for the base design. In this study design modifications are proposed and evaluated with GASFLOW in view of the hydrogen mitigation strategy.
