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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Mohamed Belhadj, Tunc Aldemir, Richard N. Christensen
Nuclear Technology | Volume 95 | Number 1 | July 1991 | Pages 95-102
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT91-A34571
Articles are hosted by Taylor and Francis Online.
Plate-type research reactor cores have involute or rectangular coolant channels with channel gap size in the range 2 ≤ d ≤ 5 mm. Heat transfer under fully developed nucleate boiling (FDNB) and low-velocity (<0.15 m/s) upward flow conditions is important in accident situations where core cooling may be by natural convection. Using data from previous experimental work with 2 ≤ d ≤ 4 mm rectangular channels, it is shown that (a) wall superheat (ΔTsat) in thin channels under FDNB decreases with increasing probability of bubble contact, (b) ΔTsat is a function of the bubble departure diameter Db as well as d, and (c) ΔTsat can be significantly overestimated by the FDNB correlations that are conventionally used in plate-type research reactor analysis but that are based on higher pressure and larger d flow data and that predict ΔTsat as a function of local channel heat flux and pressure only (e.g., as in the Jens-Lottes and Thom correlations). A new FDNB correlation is proposed that represents the bubble contact mechanism through the dimensionless number (d — cDb)/d, where c is a fitting parameter that accounts for the statistical aspects of bubble formation and contact. The ΔTsat predictions of the new correlation agree with the experimental data to within 16% and approach those obtained from the Jens-Lottes correlation with decreasing Db/d.
