ORNL completes challenging molten salt property measurements

[Marlin]

https://www.ans.org/news/2026-05-19/article-8053/ornl-completes-challenging-molten-salt-property-measurements/

[Core Content]

Researchers at Oak Ridge National Laboratory successfully measured the viscosity and thermal conductivity of uranium-bearing molten salts. These data points address existing knowledge gaps regarding how liquid fuel behaves under reactor conditions. This information supports the design and safety analysis phases for future molten salt reactor development.

Oak Ridge National Laboratory announced the completion of a set of experiments measuring the viscosity and thermal conductivity of several uranium-bearing molten salts, filling in gaps that could help with the development of molten salt reactors.

"Because fuel qualification depends on understanding how liquid fuel salts behave under reactor conditions, precise and well-characterized thermal property data is essential for MSR design and safety analysis," said Tony Birri, an ORNL research and development staff member.

According to Birri, the viscosity and thermal conductivity of uranium-bearing salts are "notoriously challenging" to measure with a high degree of accuracy because of the high temperature conditions and required materials for salt containment.

Read the full article at ans.org:
https://www.ans.org/news/2026-05-19/article-8053/ornl-completes-challenging-molten-salt-property-measurements/