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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
Katsuhei Kobayashi, Yoshiaki Fujita, Tohru Oosaki, Robert C. Block
Nuclear Science and Engineering | Volume 65 | Number 2 | February 1978 | Pages 347-353
Technical Paper | doi.org/10.13182/NSE78-A27162
Articles are hosted by Taylor and Francis Online.
The neutron average total cross section of thorium has been measured near 24 keV in an accurate transmission experiment using the time-of-flight method and the iron-filtered-beam technique. The measured average total cross section is 14.933 ± 0.041 b. The computer codes BABEL and MCROSS were used to stochastically calculate average cross sections near 24 keV from several sets of resonance parameters. The average total cross section calculated from the Forman et al. data set is in good agreement with the experimental results, but the cross section calculated from the ENDF/B-IV data set is 16% lower than the measured value. The major part of this 16% discrepancy is attributed to too small a nuclear scattering radius in the ENDF/B-IV data set.
