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Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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.
Jacopo Buongiorno, James W. Sterbentz, Philip E. MacDonald
Nuclear Technology | Volume 153 | Number 3 | March 2006 | Pages 282-303
Technical Paper | Fission Reactors | doi.org/10.13182/NT06-A3708
Articles are hosted by Taylor and Francis Online.
The supercritical water-cooled nuclear reactor (SCWR) concept offers potential for superior economics due to its high thermal efficiency and plant simplification. However, design of a thermal-spectrum core for such a reactor is complicated by the relatively low density of the water coolant and therefore reduced moderation. This requires the SCWR design to include a dedicated moderator. One solution explored worldwide is based on the use of water rods. In this paper we assess the feasibility of a different approach based on solid moderators, which has some potential advantages including increased core thermal capacity, reduced coolant worth, and simplified vessel internals. The neutronic performance of several solid moderators was evaluated and compared to that of water rods. It was found that the only acceptable solid moderator is zirconium hydride. Axial and local peaking can be readily suppressed by modest variations of the enrichment in a manner similar to the boiling water reactor practice. The Doppler and coolant reactivity coefficients are both negative and in the range of light water reactor experience. The use of zirconium hydride as a stable structural core component was evaluated and found to be acceptable under steady-state and accident conditions. In addition to its chemical and mechanical stability, zirconium hydride can also be fabricated with existing technology. However, its impact on the SCWR cost of electricity generation is deemed significant.