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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
Pegah Farshadmanesh, Tatsuya Sakurahara, Seyed Reihani, Ernie Kee, Zahra Mohaghegh
Nuclear Technology | Volume 205 | Number 3 | March 2019 | Pages 442-463
Technical Paper | doi.org/10.1080/00295450.2018.1494439
Articles are hosted by Taylor and Francis Online.
A major challenge facing the nuclear energy industry is to remain competitive under current market conditions. Utility operators are searching for innovative methods to reduce nuclear power plant (NPP) operation and maintenance costs while complying with safety and reliability requirements. To support these goals, the authors suggest a streamlined approach that implements a conservative risk-informed method to reduce the costs of satisfying emergent regulatory requirements. As a streamlined approach, the Risk-informed Over Deterministic (RoverD) method was developed by some of the authors of the current paper to resolve the concerns associated with Generic Safety Issue 191 (GSI-191). The RoverD method is designed around U.S. Nuclear Regulatory Commission Regulatory Guide 1.174 (RG 1.174), which defines “risk-informed” regulation as comprising a blend of risk-based and deterministically based elements. This paper offers the Safety Hazard Analysis for earthquaKE (SHAKE)–RoverD (SHAKE-RoverD) methodology, an extension of the original RoverD methodology developed for GSI-191, to evaluate the impact of an increased seismic hazard on the performance of NPP protective systems. SHAKE-RoverD aims to reduce the cost required for developing, validating, and documenting detailed fragility curves in seismic probabilistic risk assessment by using deterministic fragility curves. The SHAKE-RoverD methodology assesses whether an increase in a seismic hazard would result in an unacceptable increase in NPP risk. If the conservative estimate of plant risk, computed by the streamlined approach, satisfies the regulatory acceptance criteria (e.g., Regulatory Guide 1.174), the plant likely would not need to make a design change (as long as defense in depth and adequate safety margin are satisfied); therefore, the use of streamlined methodology could lead to significant cost savings for the utility operator. Future work will advance SHAKE-RoverD and analyze risk management strategies based on this method.