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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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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
Samuel E. Bays, Joseph Nielsen, Joshua Cogliati, Charles Wemple
Nuclear Technology | Volume 208 | Number 5 | May 2022 | Pages 811-821
Technical Paper | doi.org/10.1080/00295450.2021.1980320
Articles are hosted by Taylor and Francis Online.
The neutronics software, HELIOS, was validated in 2015 for performing core reload design and safety analysis of the Advanced Test Reactor. However, when HELIOS was benchmarked against historic fission-wire measurements (i.e., zero-power full-core measurements), a statistically resolved calculation-to-measurement bias was discovered. The azimuthal power along each fuel plate computed by HELIOS has consistently shown to underpredict measurements made by fission wires in historic zero-power tests near the fuel element side plates.
It was hypothesized during the HELIOS software validation work that this bias is attributable to local moderation in coolant vents in the side plates axially just above and below the fission wires on the fuel plate edges. This work used detailed MCNP and MC21 models of the side plate vents to test this hypothesis. By comparing the average azimuthal biases between HELIOS and two-dimensional and three-dimensional (3-D) MCNP models and a 3-D MC21 model, it was found that the HELIOS azimuthal bias is not due to the measurement.
