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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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!
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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
Akimaro Kawahara, Yukihiro Yonemoto, Hiroto Tazoe
Nuclear Technology | Volume 209 | Number 12 | December 2023 | Pages 1914-1928
Research Article | doi.org/10.1080/00295450.2023.2197944
Articles are hosted by Taylor and Francis Online.
This study reports the effects of the grid spacer with mixing vane (MV) on gas velocity for air single-phase flow and liquid film thickness for air-water two-phase annular flow in a 3 × 3 rod bundle channel. To investigate the effects of the shape of the spacers, three kinds of spacers were installed into the channel: spacer without MV (without MV), spacer with four MVs (4-MV30), and spacer with two MVs (2-MV30). The 4-MV30 and 2-MV30 had vanes that were inclined 30 deg from the vertical axis. Gas velocity was measured with a hot-wire anemometer and liquid film thickness was measured with the constant electric current method. From the gas velocity measurement, it was found that the irregularities in the velocity distribution became smaller toward downstream of the spacer. For the 2-MV30, the flow distribution was asymmetric and the flow was biased. From the liquid film thickness measurement, it was found that the liquid film thickness became thicker downstream of the spacer.