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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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.
Shlomo Ron, Judah Tzoref, Doron Gal
Nuclear Technology | Volume 97 | Number 3 | March 1992 | Pages 294-302
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34637
Articles are hosted by Taylor and Francis Online.
The amount of fission product release during a core heatup accident in a medium-sized high-temperature gas reactor depends on the size of the inadvertent opening in the primary circuit; this dependence is assessed. The opening triggers a depressurization event that is assumed to be coupled with the failure of the forced circulation in both decay-heat removal systems. The scenario investigated is a beyond-design-base accident. The DSNP modular simulation code is used. A two-dimensional model is developed to simulate the HTR-500 design. The study shows that the depressurization process does not contribute significantly to the sweeping out (from the primary circuit) of fission products released from the fuel during the core heatup. There is also no significant variation in the results when the opening size is >33 cm2, and only a slight sensitivity is found when the rupture size is between 3.3 and 33 cm2. The fission product release decreases considerably in the range from 1 to 3.3 cm2. The smallsized rupture is of major significance, as the failure of the relief valves to reclose increases the frequency of the event. In addition, the highest core temperature in the most severe depressurization accident scenario is evaluated, and its calculated value is lower than the graphite sublimation temperature. Although the simulation closely follows the German HTR-500 design, the conclusions may be applied to the general concept of the medium-sized high-temperature gas reactor.