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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.
John D. Burtt, Louis M. Shotkin, Joseph L. Staudenmeier
Nuclear Technology | Volume 119 | Number 3 | September 1997 | Pages 244-268
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT97-A35401
Articles are hosted by Taylor and Francis Online.
Calculations were performed for the same accident scenario in the same power plant geometry using the same version of the RELAP5/MOD3.2 computer code, but each calculation was performed using different user options in the code input deck. The accident scenario analyzed was a 1-in. cold-leg break in the new Westing-house AP600 design. The calculations were analyzed for those key events leading to actuation of the AP600 automatic depressurization system. Three different user choices for plant system noding were used: (a) a detailed noding with a quasi-three-dimensional vessel; (b) a simplified system noding with a quasi-three-dimensional core, lower plenum, and upper plenum, but a simplified downcomer noding; and (c) a detailed system and downcomer noding, but a one-dimensional core, lower plenum, and upper plenum. Two other user options were separately exercised, i.e., shutting off the model for thermal stratification and using different initial temperatures for the core. The discussion focuses on the relative effect of these different user options on flow through the P-loop hot leg, initial reversal in flow through the pressure balance line, timing of draining of the core makeup tanks, and timing of actuation of the automatic depressurization system.