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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.
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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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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.
Roberto Ponciroli, Stefano Passerini, Richard B. Vilim
Nuclear Technology | Volume 191 | Number 2 | August 2015 | Pages 151-166
Technical Paper | Reactor Safety | doi.org/10.13182/NT14-68
Articles are hosted by Taylor and Francis Online.
The recent interest in the Small Modular Reactor (SMR) for its potential increased economic competitiveness has focused attention in part on reducing operational costs to offset those plant costs that do not benefit from the economies of scale of large traditional units. Plant operation and maintenance economics are significantly driven by plant availability, which can be enhanced by means of innovative control strategies by avoiding unnecessary plant or unit trips. In this context, an effective strategy for achieving fast runback of a sodium-cooled SMR has been developed. In this work, after having defined and modeled a suitable control strategy by adopting the Petri nets formalism, a Model-based Predictive Control regulator has been developed in order to reduce as promptly as possible the power level, without scramming the reactor (fast runback) and possibly limiting the control rod contribution. Such flexibility could lead to significant savings in the operational costs of the reactor while also improving the system availability. The proposed procedure has been characterized by simulating the operational transients on both an oxide-fueled reactor and on a metal-fueled reactor, comparing the responses of the two different configurations and the respectively needed control rod contribution.