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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
Yuchuan Guo, Guanbo Wang, Dazhi Qian, Heng Yu, Bo Hu, Xiangmiao Mi, Simao Guo
Nuclear Technology | Volume 204 | Number 1 | October 2018 | Pages 15-24
Technical Paper | doi.org/10.1080/00295450.2018.1469345
Articles are hosted by Taylor and Francis Online.
A flow blockage analysis model of a single channel is established using the best-estimate code RELAP5/MOD3.4. The reactor core is divided into seven hot channels, one average channel, one bypass channel, and corresponding fuel plates to take into account the interaction between the obstructed channel and adjacent channels. The coolant system is also modeled in detail to perform a better estimation. As a typical pool-type research reactor, JRR-3M is chosen for the analysis. The results indicate that the model can effectively simulate a single-channel blockage accident using the RELAP5/MOD3.4 code. Also, the thermal-hydraulic parameters in the blocked channel would be significantly affected if bubbles are generated as the blockage ratio continues to increase, which may damage the integrity of the fuel plate. Meanwhile, as for flow blockage of a single channel, the effect on adjacent channels is limited, even under high-blockage-ratio conditions.
