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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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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BREAKING NEWS: Trump issues executive orders to overhaul nuclear industry
The Trump administration issued four executive orders today aimed at boosting domestic nuclear deployment ahead of significant growth in projected energy demand in the coming decades.
During a live signing in the Oval Office, President Donald Trump called nuclear “a hot industry,” adding, “It’s a brilliant industry. [But] you’ve got to do it right. It’s become very safe and environmental.”
Kei Ito, Daisuke Ito, Yasushi Saito (Kyoto Univ), Toshiki Ezure, Masaaki Tanaka (JAEA)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 1120-1132
A bathtub vortex is considered as one of significant phenomena which may cause gas entrainment (GE) in several industrial scenes, e.g. sodium-cooled fast reactors. In past studies, well-known Burgers vortex model is frequently used to simulate the bathtub vortex behavior. However, the Burgers model has a simple and unreal assumption that the axial velocity component is horizontally constant, while in real the bathtub vortex has the axial velocity distribution which shows large gradient in radial direction near the vortex center. In this study, a new theoretical vortex model with realistic axial velocity distribution is proposed. This model is derived from the axisymmetric Navier-Stokes equation as well as the Burgers model, but the axial velocity distribution in radial direction is considered. This function is defined to be zero at the vortex center and to approach asymptotically to zero at infinity. As the validation tests, the new model is applied to the evaluation of two simple vortex experiments and shows good agreements with the experimental data in terms of the free surface shape when the axial velocity distribution is modeled accurately. Therefore, it is confirmed that the accurate axial velocity modeling is crucially important to evaluate a bathtub vortex.