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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.
H. van Dam
Nuclear Science and Engineering | Volume 129 | Number 3 | July 1998 | Pages 273-282
Technical Paper | doi.org/10.13182/NSE98-A1981
Articles are hosted by Taylor and Francis Online.
An analysis is presented of reactor dynamics during inherent shutdown and recriticality after loss of cooling without scram. The influence of the strength of external neutron sources is studied, and the dynamics of fission product decay heat is explicitly taken into account. It is shown that decay heat and (in thermal reactors) xenon dynamics play a dominant role in inherent reactor shutdown. Fission power level at first spontaneous recriticality is determined by both the strength of the external/inherent neutron sources and the reactivity ramp rate induced by xenon decay and cooling down of the subcritical reactor core. The first power surge after recriticality is only very weakly dependent on the external/inherent neutron source strength, and the amplitude of fission power oscillations is mainly determined by the reactivity ramp rate at first recriticality. Frequency and stability of the power oscillations after recriticality depend on the thermal inertia of the core and the power-reactivity defect. Stability is slightly deteriorated by the fission product decay dynamics, but the influence of xenon dynamics is negligible.
