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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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
Tingzhou Fei, Zhaopeng Zhong, Samuel E. Bays, Florent Heidet
Nuclear Science and Engineering | Volume 196 | Number 1 | October 2022 | Pages S98-S109
Technical Paper | doi.org/10.1080/00295639.2021.1991760
Articles are hosted by Taylor and Francis Online.
The Versatile Test Reactor (VTR) is currently under development by the U.S. Department of Energy. It will provide very high fast neutron flux irradiation capabilities that are currently unavailable in the United States. Given the increasingly large number of advanced reactor concepts being pursued in recent years, this irradiation testing capability will be essential to support maturation of these designs. Radiation protection is an important part of the VTR design. High neutron fluxes can pose a challenge for radiation protection of the structures and equipment near the reactor core. This paper provides a summary on the status of the radiation protection considerations and shielding analysis performed for VTR under a nominal operating condition. The main radiation sources identified and examined in the study are applicable only under this operating condition. The paper focuses on three areas of radiation protection and shielding: secondary sodium activation in the intermediate heat exchanger, air activation in the reactor vessel auxiliary cooling system, and dose rate above the head access area due to primary sodium activation. VTR design and development are continuously progressing, and as such, the shielding considerations discussed in this paper will evolve alongside the overall VTR design.