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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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.
Mei-Ya Wang, Tsung-Kuang Yeh, Hong-Ming Liu, Min Lee
Nuclear Science and Engineering | Volume 174 | Number 2 | June 2013 | Pages 179-187
Technical Paper | doi.org/10.13182/NSE12-16
Articles are hosted by Taylor and Francis Online.
Among the six types of Generation IV reactors, the supercritical water reactor (SCWR) is the only one that adopts light water as the reactor coolant. Different from the boiling, two-phase coolant in the core of a traditional boiling water reactor (BWR), the coolant in an SCWR would remain in one phase throughout the entire primary coolant circuit (PCC) due to its much higher operating temperature (>374°C) and pressure (>22.1 MPa). For a conventional BWR, the coolant is relatively oxidizing due to the presence of hydrogen peroxide and oxygen, directly or indirectly produced via water radiolysis. This outcome eventually leads to degradation of structural materials, primarily stress corrosion cracking. In an SCWR, the solubility of oxygen in the reactor coolant is extremely high. In the absence of the gas stripping effect in a single-phase coolant, worse degradation phenomena are expected to appear in the structural and core components. To ensure proper designs of the structural components and suitable selection of the materials to meet the requirements of operation safety, it would be of great assistance to the design engineers of an SCWR to be aware of the intrinsic state of water chemistry in the entire PCC. Since SCWRs are still at the stage of conceptual design and no practical data are available, a computer model was developed for determining the water chemistry variation and the corrosion behavior of metallic materials in the PCC of a conceptual SCWR. Radiolysis parameters used for calculating the concentrations of major redox species (i.e., [O2], [H2], and [H2O2]) in the reactor coolant were collected from literature reports. However, the lack of sufficient data necessitated that some were derived by extrapolation. Calculations indicated that the concentrations of the two major oxidizing species (H2O2 and O2) could become extremely high at locations inside or near the core, considerably higher than those in typical BWRs. It was therefore speculated that the structural materials in an SCWR may be exposed to an environment not only at a much higher temperature but also one that is more oxidizing than that in a conventional BWR.
