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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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.
B. M. Abraham, H. E. Flotow, R. D. Carlson
Nuclear Science and Engineering | Volume 2 | Number 4 | July 1957 | Pages 501-512
Technical Paper | doi.org/10.13182/NSE57-A25415
Articles are hosted by Taylor and Francis Online.
Suspensions of UO2 in NaK alloy are being studied as possible reactor fuels. Two loops have so far been constructed of one-half inch stainless steel tubing with a test volume of approximately 150 cc. The Mark I loop was operated for 400 hours between 450 and 600°C, while circulating a slurry of 4.3 volume % UO2 (36.0 weight per cent). The radioactive monitor indicated that the slurry was uniformly suspended at a flow rate of 2 ft/sec. It was found that above 500°C the UO2 dropped out of suspension, but was immediately resuspended when the temperature dropped below the critical value of 500°C. The effect was reversible and could not be eliminated even at the fastest flows. The Mark II loop incorporated a density measuring device in order to correlate the radioactivity monitor with the density of the slurry. It was found, as previously suspected, that when the counts reached maximum value the density also was a maximum, at the calculated value. One gram of powdered uranium metal added to the loop with the UO2 completely eliminated the settling above 500°C observed in the Mark I loop. There was no evidence for corrosion or erosion of the loop, and the particle size of UO2 was practically unchanged after operation at the high temperature. The UO2 could be resuspended immediately after prolonged settling.