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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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
Elmar Eidelpes, Luis F. Ibarra, Ricardo A. Medina
Nuclear Technology | Volume 205 | Number 8 | August 2019 | Pages 1095-1118
Regular Technical Paper | doi.org/10.1080/00295450.2019.1575127
Articles are hosted by Taylor and Francis Online.
This study presents two statistical models that were developed to estimate the expected peak cladding hoop stress (CHS) and the amount of hydrogen in pressurized water reactor (PWR) spent nuclear fuel (SNF) rod cladding. Peak CHS is caused by high rod internal pressure during vacuum drying performed when transferring SNF to dry storage. During in-reactor operation of PWR fuel, the rod cladding tends to corrode and uptake hydrogen. The hydrogen content and CHS control hydride-related cladding embrittlement at low material temperatures. The two methodologies developed in this study were used to create a generic rod database with information on PWR SNF conditions. This database provides information on 100 000 randomly selected rods that form part of the current U.S. SNF inventory. According to the statistical results, the expected hydrogen content of PWR rod cladding is in a sensitive interval that may facilitate hydride reorientation. However, the modeling results suggest that the expected peak CHS of the selected rods is significantly below 90 MPa, which is the estimated lower bound stress necessary to trigger significant radial hydride embrittlement in cladding after being cooled to room temperature. Further, the results indicate that hydride embrittlement due to excessive hydrogen in cladding is unlikely. Therefore, a low probability of hydride-related embrittlement of PWR SNF cladding currently stored in the U.S. inventory is anticipated, even under consideration of low cladding temperatures after long-term SNF dry storage.