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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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
Thiago D. Roberto, Celso M. F. Lapa, Antonio C. M. Alvim
Nuclear Technology | Volume 206 | Number 4 | April 2020 | Pages 527-543
Technical Paper | doi.org/10.1080/00295450.2019.1666603
Articles are hosted by Taylor and Francis Online.
Reactor cavity cooling systems (RCCSs) ensure the physical integrity of the containment structures in a high-temperature gas-cooled test reactor (HTR-10) and a high-temperature gas-cooled pebble-bed module reactor (HTR-PM). HTR-10 is a graphite-moderated and helium-cooled pebble-bed reactor prototype designed to demonstrate the technical feasibility and safety of the pebble-bed reactor design concept under normal and accident conditions. This prototype served as a proof of concept for the HTR-PM that shares several design similarities with the HTR-10, including a reactor cavity that requires cooling owing to the high core outlet temperature. The RCCS conceived in the design of both the reactors increases the inherent safety of the system by dissipating heat through passive heat removal processes. This paper proposes an RCCS model for system-scale analysis. The conventional scale method is adopted to determine the conditions necessary for complete similarity between two RCCSs in the steady-state flow regime. In addition, a scaling evaluation between the RCCSs of both the HTR-10 (model) and HTR-PM (prototype) is performed using the proposed RCCS model based on data from two benchmark problems: pressurized and depressurized loss of forced cooling. This evaluation shows that the RCCSs of the HTR-10 (model) and HTR-PM (prototype) show similarity to a specific operational condition in each of the problems analyzed.