ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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
20th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-20)
Cofounder and Chief Technology Officer
NuScale Power
José N. Reyes, Ph.D., co-founded NuScale Power, LLC, co-designed the NuScale passively-cooled small nuclear reactor and has served as the company’s Chief Technology Officer since 2007. Dr. Reyes is an internationally recognized expert on passive safety system design, testing and operations for nuclear power plants. He has served as a United Nations International Atomic Energy Agency technical expert on passive safety systems, is a co-inventor on more than 180 patents granted or pending in 20 countries and has received several national awards including the 2013 Nuclear Energy Advocate Award, the 2014 American Nuclear Society Thermal Hydraulic Division Technical Achievement Award, the 2017 Nuclear Infrastructure Council Trailblazer Award, the 2021 American Nuclear Society Walter H. Zinn Medal, and 2021 inductee into the University of Maryland Innovators Hall of Fame.
Dr. Reyes is a fellow of the American Nuclear Society (ANS), a NURETH fellow, and a member of the National Academy of Engineering. In the past, he has served as head of the Oregon State University (OSU) Department of Nuclear Engineering and Radiation Health Physics, directed the Advanced Thermal Hydraulic Research Laboratory and was the Co-Director of the Battelle Energy Alliance Academic Center of Excellence for Thermal Fluids and Reactor Safety in support of the Idaho National Laboratory mission.
Dr. Reyes currently serves as a Professor Emeritus in OSU’s School of Nuclear Science and Engineering. He holds Ph.D. and Master of Science degrees in nuclear engineering from the University of Maryland and a Bachelor of Science degree in nuclear engineering from the University of Florida. He is the author of numerous journal articles and technical reports, and he has given lectures and keynote addresses to professional nuclear organizations in the United States, Europe and Asia. He is a licensed professional engineer in the state of Oregon.
Patents (180 Patents Granted or Pending in 20 Countries):
Keynote Speaking Engagements in 2022:
Last modified August 1, 2023, 10:20am EDT