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
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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
Apr 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
May 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Glass strategy: Hanford’s enhanced waste glass program
The mission of the Department of Energy’s Office of River Protection (ORP) is to complete the safe cleanup of waste resulting from decades of nuclear weapons development. One of the most technologically challenging responsibilities is the safe disposition of approximately 56 million gallons of radioactive waste historically stored in 177 tanks at the Hanford Site in Washington state.
ORP has a clear incentive to reduce the overall mission duration and cost. One pathway is to develop and deploy innovative technical solutions that can advance baseline flow sheets toward higher efficiency operations while reducing identified risks without compromising safety. Vitrification is the baseline process that will convert both high-level and low-level radioactive waste at Hanford into a stable glass waste form for long-term storage and disposal.
Although vitrification is a mature technology, there are key areas where technology can further reduce operational risks, advance baseline processes to maximize waste throughput, and provide the underpinning to enhance operational flexibility; all steps in reducing mission duration and cost.
J. Pacio, M. Daubner, T. Wetzel (KIT)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 520-530
For the design and licensing of innovative reactor concepts, the thermal-hydraulic assessment must consider both nominal conditions and postulated accidental scenarios. For the LBE-cooled MYRRHA reactor, developed at SCK•C EN (Belgium), one postulated event with low, yet non-negligible probability of occurring is the presence of local blockages in a fuel assembly. If the pins in the active region cannot be cooled efficiently, local hot spots can potentially lead to cladding failure.
In this work, thermal-hydraulic tests in a rod bundle with local blockages were performed at a large-scale LBE experimental facility at KIT (Germany), on a 19-rod bundle with wire spacers, as part of the European project MAXSIMA. The geometry, operating conditions, and blockages characteristics are representative of postulated worst-case scenarios for the MYRRHA reactor. In particular, small blockages with low thermal conductivity are studied, indicative of oxide particles accumulating along the spacers.
Local temperatures are obtained at selected wall and fluid locations, for the validation of simulations. Moreover, a semi-empirical correlation is developed for estimating the maximum wall overheat, which can be significant for blockages covering several sub-channels. Furthermore, differential pressure measurements indicate that small blockages have a negligible effect in the global relation between flow and pressure drop, and thus cannot be detected at the fuel assembly outlet.