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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.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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ANS announces 2025 Presidential Citations
One of the privileges of being president of the American Nuclear Society is awarding Presidential Citations to individuals who have demonstrated outstanding effort in some manner for the benefit of ANS or the nuclear community at large. Citations are conferred twice each year, at the Annual and Winter Meetings.
ANS President Lisa Marshall has named this season’s recipients, who will receive recognition at the upcoming Annual Conference in Chicago during the Special Session on Tuesday, June 17.
Luis Palomino, Mohamed S. El-Genk
Nuclear Technology | Volume 195 | Number 1 | July 2016 | Pages 1-14
Technical Paper | doi.org/10.13182/NT15-102
Articles are hosted by Taylor and Francis Online.
The Scalable LIquid Metal–cooled small Modular (SLIMM) reactor generates 10 to 100 MW(thermal) for extended periods without refueling. With the aid of an in-vessel chimney and a Na/Na helically coiled tubes heat exchanger (HEX) in the downcomer, natural circulation of in-vessel liquid sodium cools the SLIMM reactor core during nominal operation and after shutdown. With an unlikely malfunction of the Na/Na HEX, natural circulation of ambient air along the outer surface of the guard vessel wall maintains in-vessel natural circulation of liquid sodium and passively removes the decay heat after reactor shutdown. This paper performs three-dimensional computational fluid dynamics and thermal-hydraulic analyses to obtain preliminary estimates of the rate of decay heat removal by ambient air in case of a malfunction of the in-vessel Na/Na HEX and investigates the effect of using longitudinal metal fins along the guard vessel outer surface. The analyses calculate the contributions of natural convection and thermal radiation to the rate of decay heat removal by ambient air. For the same sodium temperatures in the reactor vessel downcomer as during steady-state nominal operation at 100 MW(thermal), the decay heat removal rate by ambient air without metal fins is ~1.0 MW(thermal), increasing by 26% to 1.26 MW(thermal) with metal fins. The contributions of natural convection and thermal radiation to the rate of decay heat removal are 58% and 42% without metal fins and 70% and 30% with metal fins, respectively. Extending the metal fins an additional 5 m and doubling the axial thermal conductivity increase the rate of the decay heat removal only slightly, to 1.28 MW(thermal).