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2025 ANS Annual Conference
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Chicago, IL|Chicago Marriott Downtown
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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
Jordan Crowell, Eleodor Nichita
Nuclear Technology | Volume 209 | Number 4 | April 2023 | Pages 504-514
Technical Paper | doi.org/10.1080/00295450.2022.2135334
Articles are hosted by Taylor and Francis Online.
Small Canadian arctic communities rely on diesel generators for their electricity needs. Providing such generators with fuel year round presents logistical challenges because of inclement weather and the long transportation distances involved. This work presents the conceptual design of a 10-MW(thermal) microreactor that can be used to provide 3.5 MW of electricity as well as district heating to arctic communities. The reactor has a lead-cooled and graphite-moderated core with 13 vertical fuel channels containing high-assay low-enriched uranium fuel enriched to 10%. The core is enclosed in a unpressurized reactor vessel and is passively cooled through natural convection. Stirling engines are used to drive the electrical generators. The hot cylinders of the Stirling engines are located in the unpressurized reactor vessel and are heated directly by the primary coolant. Preliminary neutronic and thermal-hydraulic analyses of the core indicate that the design is technically feasible and that the reactor can function for 2 years and 9 months without refueling.