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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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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.
Kazys K. Almenas, Yih-Yun Hsu, Marino Dimarzo, Zen-You Wang, Gary A. Pertmer, Richard Lee
Nuclear Technology | Volume 82 | Number 3 | September 1988 | Pages 341-354
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34135
Articles are hosted by Taylor and Francis Online.
A sufficiently large data base of repeated integral thermal-hydraulic loop tests has been accumulated recently from which generalized conclusions can be drawn. Evidence obtained from experiments performed in the University of Maryland College Park (UMCP) loop show that qualitative as well as quantitative differences exist between integral and separate effect tests. For separate effect tests, flow conditions are controlled continuously and usually steady (or quasi-steady) states are of interest. Integral facilities are “closed” systems and reactor safety oriented investigations center on transient behavior for which only initial conditions can be specified. It is shown that integral flow systems have a generic capability of amplifying (or damping) small perturbations and usually can operate in one of several possible alternate flow states. These characteristics can lead to two distributions of interexperiment variations; the differences can follow a Gaussian distribution or a bifurcation. In the UMCP test program, several examples of repeat experiments whose trajectories fall outside a Gaussian distribution were observed. Such experimental results have implications for the planning of experimental test programs and for the verification process of computational models.