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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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
D. D. Lisowski, T. C. Haskin, A. Tokuhiro, M. H. Anderson, M. L. Corradini
Nuclear Technology | Volume 183 | Number 1 | July 2013 | Pages 75-87
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT13-A16993
Articles are hosted by Taylor and Francis Online.
Recent design efforts have used the reactor cavity cooling system (RCCS) for passive decay heat removal in the Next Generation Nuclear Plant. Employing a series of riser tubes and cooling panels that line the containment walls, the RCCS can provide an ultimate heat sink for decay power removal from the system without the need for AC power. With vessel wall temperatures expected to reach 450°C, intuition suggests that radiation will be the dominant mode of heat transfer. However, the authors show that several factors can alter these modes; variations in cavity height, riser tube geometry, and vessel heat flux may have significant roles in the heat removal by the RCCS.The authors have constructed a one-quarter-scale water-cooled experimental facility at the University of Wisconsin-Madison that is based on available open literature of the General Atomics modular high-temperature gas-cooled reactor, with a three-riser tube and cooling panel test section representing a 5-deg slice of the full-scale design. Under prototypic heat flux conditions, a series of scoping tests with linear and asymmetrically skewed heating profiles were performed to investigate the split in flow distribution among the parallel channels. Numerical results, using RELAP5 models and FLUENT simulations, provide a comparison to experimental data sets and insight into the split among heat transfer modes present in the cavity.Application of these passive decay heat removal systems demands a pragmatic approach that can account for the irregularities and nonuniformities present in a real design. In areas of blocked views, such as near support structures and primary cooling pipes, convection can provide a mechanism to smooth the otherwise skewed radiative heat flux for heat transfer from the reactor pressure vessel walls to the cooling panels. Integral to the design of the RCCS, the cooling fins serve to protect the cavity wall while adding additional pathways for heat dissipation by conduction into the cooling tubes.