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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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.
H.-M. Prasser, M. Beyer, A. Böttger, H. Carl, D. Lucas, A. Schaffrath, P. Schütz, F.-P. Weiss, J. Zschau
Nuclear Technology | Volume 152 | Number 1 | October 2005 | Pages 3-22
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT05-A3657
Articles are hosted by Taylor and Francis Online.
Air-water two-phase flow tests in a large vertical pipe of 194.1-mm inner diameter (i.d.) are reported. Close to the outlet of a 9-m-tall test section, two wire-mesh sensors are installed that deliver instantaneous void fraction distributions over the entire cross section with a resolution of 3 mm and 2500 Hz used for fast-flow visualization. Void fraction profiles, gas velocity profiles, and bubble-size distributions were obtained. A comparison to a small pipe of 52.3-mm i.d. (DN50) revealed significant scaling effects. Here, the increase of the airflow rate leads to a transition from bubbly via slug to churn-turbulent flow. This is accompanied by an appearance of a second peak in the bubble-size distribution. A similar behavior was found in the large pipe; though the large bubbles have a significantly larger diameter at identical superficial velocities, the peak is less high but wider. These bubbles move more freely in the large pipe and show more deformations. The shapes of such large bubbles were characterized in three dimensions. They can be rather complicated and far from ideal Taylor bubbles. Also, the small bubble fraction tends to bigger sizes in the large pipe.