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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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.
I. Otic, G. Grötzbach
Nuclear Science and Engineering | Volume 155 | Number 3 | March 2007 | Pages 489-496
Technical Paper | Mathematics and Computation, Supercomputing, Reactor Physics and Nuclear and Biological Applications | doi.org/10.13182/NSE07-A2679
Articles are hosted by Taylor and Francis Online.
Results of a direct numerical simulation (DNS) for Rayleigh-Bénard convection for the Rayleigh number Ra = 105 in a fluid with the Prandtl number Pr = 0.025, which corresponds to liquid lead-bismuth, are used to analyze the turbulent heat flux and the temperature variance dissipation rate. The results indicate that application of a thermal or a mixed timescale may considerably improve gradient diffusion and algebraic heat flux models at these Rayleigh and Prandtl numbers. Therefore, a good approximation of the temperature variance dissipation rate is required. The standard temperature variance dissipation rate model is investigated using the DNS results. The analysis of the standard model shows the importance of wall functions and qualitatively good predictions by the model for this type of flow. Quantitatively, the model overpredicts the temperature variance dissipation rate evaluated from the results of DNS by ~25%. The two-point correlation method is used to derive new models for the temperature variance dissipation rate. Comparison with DNS results shows qualitatively and quantitatively good predictions by the new models. These new models lead therefore to an increased accuracy of the turbulent heat flux models for this type of flow.