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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.
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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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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
N. Chikhi, P. Fouquart, J. Delacroix, P. Piluso
Nuclear Technology | Volume 205 | Number 1 | January-February 2019 | Pages 200-212
Technical Paper | doi.org/10.1080/00295450.2018.1486160
Articles are hosted by Taylor and Francis Online.
In-vessel retention (IVR) is an attractive strategy to mitigate a severe accident. However, because of low margins, it remains questionable for reactors of power of 1000 MW(electric) and higher. The success of the IVR strategy mainly depends on the mechanical behavior of the vessel after being ablated and on the inner thermal load, i.e., the heat flux transferred by the molten pool to the vessel, which has to remain lower than the critical heat flux. In some configurations, the stratification of the molten pool may lead to heat flux concentration in the thermal conductive metallic layer. An understanding of the metal layer behavior is fundamental in order to estimate the inner thermal load and requires knowing the liquid-metal physical properties, such as density and surface tension. In the present paper, original data of vessel thermophysical properties are proposed for the first time. Measurements of Type 304L stainless steel and 16MND5 ferritic steel density and surface tension have been made using the sessile drop method. Samples have been melted to form a drop on a yttria-stabilized zirconia substrate and heated up to 200°C above the melting point. Low Bond Axisymmetric Drop Shape Analysis has been used to estimate the sample density and surface tension and to propose correlations for the density and surface tension as a function of temperature. The influence of steel properties on metal layer cooling has been discussed. Especially, the sign of the metal temperature surface tension coefficient was found to be most likely positive. In this case, the Bénard-Marangoni flow is opposite to the Rayleigh-Bénard convection flow.