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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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.
Michael R. Prisco, Robert E. Henry, Michael N. Hutcherson, John L. Linehan
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 365-375
Technical Paper | doi.org/10.13182/NSE77-A27054
Articles are hosted by Taylor and Francis Online.
Two-phase, critical flow data are reported for initially saturated and subcooled liquid Freon-11 flowing through sharp-edged entrance tubes for length-to-diameter (L/D) ratios from 2.82 to 100. Comparisons among various analytical models and these data show that nonequilibrium models describe the critical flow phenomenon more accurately than equilibrium models. It is shown that to obtain reliable exit plane pressure measurements, it is necessary to have a gradual divergence at the exit of the constant-area tube. This minimizes the expansion of the exiting fluid, which would otherwise result in an exit pressure measurement much lower than the one-dimensional value governing the flow. Utilizing data from this study, quantitative estimates of the individual phase velocities at the condition of critical flow indicate that “vapor choking” is not the mechanism by which two-phase critical flow occurs in this investigation. The flow pattern in a transparent test section, with an L/D ratio of 2.82, has been observed and photographed, and this shows that the separated flow condition (liquid jet surrounded by vapor) begins to break up into a dispersed two-phase mixture approximately one equivalent diameter downstream of the entrance.