ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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
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!
Latest Magazine Issues
May 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
July 2025
Nuclear Technology
June 2025
Fusion Science and Technology
Latest News
High-temperature plumbing and advanced reactors
The use of nuclear fission power and its role in impacting climate change is hotly debated. Fission advocates argue that short-term solutions would involve the rapid deployment of Gen III+ nuclear reactors, like Vogtle-3 and -4, while long-term climate change impact would rely on the creation and implementation of Gen IV reactors, “inherently safe” reactors that use passive laws of physics and chemistry rather than active controls such as valves and pumps to operate safely. While Gen IV reactors vary in many ways, one thing unites nearly all of them: the use of exotic, high-temperature coolants. These fluids, like molten salts and liquid metals, can enable reactor engineers to design much safer nuclear reactors—ultimately because the boiling point of each fluid is extremely high. Fluids that remain liquid over large temperature ranges can provide good heat transfer through many demanding conditions, all with minimal pressurization. Although the most apparent use for these fluids is advanced fission power, they have the potential to be applied to other power generation sources such as fusion, thermal storage, solar, or high-temperature process heat.1–3
Youngsu Na
Nuclear Technology | Volume 211 | Number 2 | February 2025 | Pages 273-285
Research Article | doi.org/10.1080/00295450.2024.2325738
Articles are hosted by Taylor and Francis Online.
This study evaluates the spatial dilution of hydrogen concentration caused by steam-hydrogen buoyancy jets rising through the open top of the steam generator compartment during a loss-of-coolant accident in the OPR1000, the Korean Standard Nuclear Power Plant. The correlation of the concentration decay rate in the plume with relatively high buoyant flux was applied to estimate the hydrogen concentration in the rise distance of the buoyant jet. The MELCOR code was used to calculate the gas composition and discharge flow rate in the ruptured cold leg during the rapid cladding oxidation to determine the volume and buoyant fluxes that affect the mixing behavior. The concentration decay rate at the plume’s center decreases as the steam-hydrogen binary buoyant jet rises. Despite the assumed initial volume flux and simplified jet nozzle geometry, the decay rate correlation can assess conservatively the diluted hydrogen in a severe accident.
