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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.
Meeting Spotlight
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
W. J. McCool, R. A. Robinson, E. W. Schrader, S. H. Weiss
Nuclear Science and Engineering | Volume 9 | Number 1 | January 1961 | Pages 47-54
Technical Paper | doi.org/10.13182/NSE61-A25864
Articles are hosted by Taylor and Francis Online.
The cold, clean, steel-reflected, final, SM-2 mock-up containing 36.4 kg U235 and 61 g B10 maintained criticality after a seven rod bank withdrawal of 6.974 in. and has an “excess K” (ΔKE) of 1520 cents. An infinite steel-water laminated reflector is worth approximately +85 cents over the infinite water reflected core. The measured reactivity coefficient, @ 2000 psi, ranges from –1.15 cents/°F @ 150°F to –5.20 cents/°F @ 510°F. The integral reactivity effect of raising the SM-2 core water temperature from 103 to 510°F @ 2000 psi and the water in the reflector coolant graph from 103 to 477°F @ 2000 psi is –889.7 cents. The average measured material coefficients for U235 and B10 are 0.157 cents/g and 42.54 cents/g, respectively. Without the benefit of flux suppressors the maximum to average power ratio of 7.28 occurs at the top of the fuel section of control rod C (withdrawn to 7.14 in.), and a ratio of 5.28 occurs at the bottom of stationary element 43 and symmetric elements.
