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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.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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Fusion Science and Technology
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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
P. Hennequin
Fusion Science and Technology | Volume 41 | Number 2 | March 2002 | Pages 234-241
Transport and Instabilities | doi.org/10.13182/FST02-A11963522
Articles are hosted by Taylor and Francis Online.
Fluctuations are usually invoked to explain the anomalous transport in tokamaks. The main observations regarding fluctuating quantities obtained in a wide range of experiments are summarised. Fluctuations are turbulent with broad wavenumber and frequency spectra, the wavenumber being such that kχL, < 1 and frequencies in the diamagnetic drift frequency range. Density, potentiel and temperature (electrostatic) fluctuations at the edge are generally observed to account for particle and energy transport. This direct comparison cannot be done in the core because of the limited available measurements, and fluctuation driven transport is to be estimated through the various theories. However the fluctuation level is generally observed to be correlated with the transport properties in a wide range of regimes. In particular in improved confinement regimes with transport barriers, turbulence is drastically reduced, magnetic/velocity shear are identified as the control parameters.
