ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Mathematics & Computation
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.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
May 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
July 2025
Nuclear Technology
June 2025
Fusion Science and Technology
Latest News
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
Helen Winberg-Wang
Nuclear Technology | Volume 204 | Number 2 | November 2018 | Pages 184-194
Technical Paper | doi.org/10.1080/00295450.2018.1469348
Articles are hosted by Taylor and Francis Online.
Diffusion experiments under stagnant conditions in a constant aperture and a variable aperture slot were made to obtain data for simulation of simultaneous flow and diffusion in fractures. This approach was necessitated by the need to avoid buoyancy-induced flow caused by density differences generated by the presence of a tracer. For this purpose, to avoid flow but negligibly influence diffusion the slots were filled with agar, which generates a 99% porous matrix, which negligibly affects diffusion but essentially stops flow. A simple photographic technique was used to follow diffusion and to determine the aperture distribution on the variable aperture slot. With the obtained data, numerical simulations were performed to illustrate how a solute diffuses from a source into the water seeping past. The results support the simple analytical solution that has been used to determine the escape of radionuclides from a damaged canister containing spent nuclear fuel in a geologic repository in fractured rock.
