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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.
Hiroshige Kumamaru, Yutaka Kukita, Hideaki Asaka, Ming Wang, Etsuo Ohtani
Nuclear Technology | Volume 126 | Number 3 | June 1999 | Pages 331-339
Technical Note | Thermal Hydraulics | doi.org/10.13182/NT99-A2978
Articles are hosted by Taylor and Francis Online.
The effectiveness of intentional depressurization of a pressurized water reactor primary system as a means to maintain core cooling during a small-break loss-of-coolant accident (SBLOCA) was studied. The investigation was based on experiments conducted at the Rig of Safety Assessment-V (ROSA-V) Large Scale Test Facility (LSTF) and RELAP5/MOD3 code calculations performed for LSTF geometry, together with single lumped-volume model calculations - all simulating hypothetical total failure of the high-pressure-injection system. For cold-leg breaks ≶2.5% of the leg cross-sectional area, experimental and analytical results have shown that the break discharge depressurizes the primary system to the accumulator (ACC) and low-pressure-injection (LPI) system injection pressures, and thus the core cladding temperature would be maintained below ~1000 K. For break areas ≤1.0%, on the other hand, additional depressurization means are needed to initiate the ACC injection before the core is overheated. RELAP5/MOD3 calculations have shown that steam venting through the pressurizer power-operated relief valves would be effective in depressurizing the primary system to the ACC and LPI pressures. However, for break areas <0.5%, the peak cladding temperature would finally reach the safety criterion of 1473 K.