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The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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
P. T. Guenther, D. G. Havel, A. B. Smith
Nuclear Science and Engineering | Volume 65 | Number 1 | January 1978 | Pages 174-180
Technical Note | doi.org/10.13182/NSE78-A27140
Articles are hosted by Taylor and Francis Online.
Differential elastic neutron scattering cross sections of 206Pb, 207Pb, 208Pb, and 209Bi are measured at incident neutron energy intervals of ∼25 keV from 0.6 to 1.0 MeV. Optical model parameters are obtained from the energy-averaged experimental results for each of the isotopes. The 209Bi model was selected for extrapolation to 238U by introducing a small (N - Z)/A dependence and the known deformation of 238U. Calculated results are descriptive of 238U total neutron cross sections from a few hundred keV to >15.0 MeV and of recently measured differential 238U elastic and inelastic neutron scattering distributions at energies of 3.0 MeV, including new experimental values explicitly obtained for these comparisons. The model and the measurements imply total 238U inelastic neutron scattering cross sections considerably larger than in common applied usage.
