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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
S. Suyambazhahan, T. Sundararajan, Sarit K. Das
Nuclear Science and Engineering | Volume 197 | Number 3 | March 2023 | Pages 413-427
Technical Paper | doi.org/10.1080/00295639.2022.2116380
Articles are hosted by Taylor and Francis Online.
Thermal striping is associated with random fluctuations of temperature that occur at the nonisothermal jet stream interface or across thermally stratified fluid layers due to the high heat transfer coefficient of liquid sodium flow. The temperature fluctuations in the jet mixing or stratified layer regions are transmitted to the adjoining structures after minimal attenuation in a Liquid Metal Fast Breeder Reactor (LMFBR). In turn, the adjoining structure may experience high cycle fatigue and catastrophic failure caused by crack propagation. Investigations have been carried out in detail numerically, and frequency and amplitude of temperature fluctuations in 500-MW(electric) pool-type fast reactor [Prototype Fast Breeder Reactor (PFBR)] structures for practical applications have been observed. The investigations consist of numerical simulations at two levels. First, a published benchmark experiment is analyzed, and then, a suitable computational fluid dynamics (CFD) model is identified for simulating the thermal striping phenomenon numerically. After that, detailed flow and temperature fluctuations are predicted in the reactor structures by analysis carried out based on the CFD model. The values of the temperature fluctuations predicted are found to be within acceptable limits, as required by structural mechanics considerations in the study.