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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.
Lianfa Wang, Mingjun Wang, Suizheng Qiu, Guanghui Su, Wenxi Tian (Xi’an Jiaotong Univ)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 33-43
The lateral flow in top core region and upper plenum is detrimental for power control. The temperature heterogeneity in hot-legs induces the deviation of estimation of power level. Therefore, to investigate the lateral flow at the core outlet and temperature heterogeneity in the hot-legs of AP1000, a CFD analysis of the domain from the core inlet to hot-leg outlet was conducted. The core region was simulated by introducing additional source term in the momentum equations instead of being reconstructed in detail. A volumetric power density of hot full power derived from AP1000 middle of life was applied to the active core zone. The main internal components including control guide tubes with eight large opening windows on it and support columns were kept, while other little components including control rod assemblies were omitted to decrease the total mesh quantity. The Reynolds-averaged Navier-Stokes equations was solved with Realizable k-? turbulence model using commercial CFD code FLUENT. The coolant temperature map at the core outlet and the extent of the hot-leg suction effect on the top core region were obtained. Compared with the temperature field at core outlet, the maximum temperature difference at the entrance of the hot-leg drops 10K after the mixing in the upper plenum. The hotter coolant from central fuel assemblies remains at the upper part of the hot-leg, while the cooler coolant from peripheral fuel assemblies stays in the lower part of the hot-leg. The temperature heterogeneity and its evolvement along the hot-leg were analyzed.