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
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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
Ilyas Yilgor, Eymon Lan, Shanbin Shi
Nuclear Science and Engineering | Volume 197 | Number 5 | May 2023 | Pages 753-770
Technical Paper | doi.org/10.1080/00295639.2022.2087835
Articles are hosted by Taylor and Francis Online.
Interest in heat pipe microreactors (HPMRs) has recently grown due to several unique advantages compared with other reactor types. These compact and mobile reactors are expected to find applications in a variety of fields to provide carbon-free power in remote or off-grid locations. Experimental work is needed to aid and expedite the design and licensing of future HPMRs, especially on the validation of heat pipe performance as key heat transfer components. A Low-Temperature Heat Pipe Test Facility (LTHPF) was designed and constructed according to previously developed scaling laws to bypass the difficulties of experimenting with liquid-metal working fluids by using surrogate fluids. The design, instrumentation, and experimental capabilities of the facility are described. The testing conditions, including various operating limits and the ranges of the nondimensional parameters used for scaling analysis, are reported. It is found that certain nondimensional parameters could yield a wide range over the operating conditions, whereas some showed minimal variation when water was used as the working fluid. Last, the performance of several types of wicks, including the annulus-screen, groove-screen, and wrapped-screen designs, were investigated for applications in the LTHPF. It is observed that the groove-screen wick structure provided slight improvement in capillary limits at higher temperatures and that the wrapped-screen wick yielded lower capillary limits due to the absence of a low-resistance flow path for the liquid.