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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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.
Rakesh Chawla, Om Parkash Joneja, Marc Rosselet, Tony Williams
Nuclear Technology | Volume 139 | Number 1 | July 2002 | Pages 50-60
Technical Paper | Reactor Safety | doi.org/10.13182/NT02-A3303
Articles are hosted by Taylor and Francis Online.
Although high-temperature reactors (HTRs) are endowed with a number of inherent safety features, there are still aspects of the design that need particular attention. For concepts in which shutdown rods are situated outside the core region, as is the case in contemporary modular pebble bed designs, accurate calculations are needed for the worth of these shutdown rods not only in normal operation but also under accident conditions in which significant changes occur, for instance, due to inadvertant moderation increase in the core (ingress of water or other hydrogeneous compound). Corresponding validation experiments, employing a variety of reactivity measurement techniques, were conducted in the framework of the HTR-PROTEUS program employing low-enriched uranium pebble-type fuel. Details of the experimental configurations, along with the measurement results obtained, are given for two different HTR-PROTEUS cores, in each of which four different shutdown rod combinations were investigated. Comparisons made with calculations, based on both approximative deterministic models and geometrically "near-to-exact" Monte Carlo analyses, have clearly brought out the sensitivity of the experimental results to calculational correction factors when conventional (thermal) techniques are used for reactivity measurements in such systems. Considerably greater systematic accuracies are reflected in the experimental shutdown rod values obtained using specially developed epithermal techniques, and it is these results that are recommended for benchmarking purposes.