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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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.
Jack Chernick
Nuclear Science and Engineering | Volume 1 | Number 2 | May 1956 | Pages 135-155
Technical Paper | doi.org/10.13182/NSE56-A17518
Articles are hosted by Taylor and Francis Online.
The nuclear properties and potentialities of small liquid metal fueled reactors (LMFR) are presented. Plutonium is discussed as an alternate fuel to uranium isotopes, lead as alternate carrier to bismuth, and beryllium as alternate moderator to graphite. Breeding potentialities of U233 and Pu239 fueled liquid metal systems are discussed. It is shown that non-breeder cores can be reduced to about 1 to 4 ft in diameter, depending on fuel concentration and core and reflector compositions. Internal versus external cooling and internal versus external moderation of the small LMFR are compared. Internally moderated reactors have a more complex core but require less fissionable material. For LMFR cores externally moderated by graphite, the critical mass requirements are found to be relatively constant over a wide range of fuel concentrations with a minimum of about 10 kg for U233 fuel. For small LMFR cores, heat transfer rather than heat transport is the only bar to extremely high specific power in power applications and to high neutron flux in research applications. Externally cooled reactors, coupled to conventional heat exchangers require a large external holdup of the liquid metal, thus putting a premium on low fuel concentrations. Internally cooled LMFR's with graphite (or beryllium) moderation and heat exchange require advances in present technology. Sodium is an attractive coolant for an internally cooled, externally moderated version of the LMFR with slurry type fuel elements. It is pointed out that, for research applications, the flux level achievable in a thermal reactor with fixed power output has about reached its practical limit. This is not the situation for intermediate energy reactors. In particular, it is shown that an intermediate energy LMFR can achieve an average core flux of 1015 neutrons/cm2-sec at 10 Mw power output. Finally, integral experiments and neutron cross sections needed for firm estimates of the conversion ratios and critical mass requirements of LMFR systems, especially for weakly moderated systems, are discussed.