Velocity Profile Measurement of Lead-Lithium Flows by High-Temperature Ultrasonic Doppler Velocimetry

Y. Ueki, M. Hirabayashi, T. Kunugi, K. Nagai, J. Saito, K. Ara, N. B. Morley

Fusion Science and Technology | Volume 60 | Number 2 | August 2011 | Pages 506-510

Plasma Engineering - Fueling and Diagnostics | Proceedings of the Nineteenth Topical Meeting on the Technology of Fusion Energy (TOFE) (Part 2) | doi.org/10.13182/FST60-506

Articles are hosted by Taylor and Francis Online.

This paper describes a high-temperature ultrasonic Doppler Velocimetry (HT-UDV) technique that has been successfully applied to measure velocity profiles of the lead-lithium eutectic alloy (PbLi) flows. The impact of tracer particles is investigated to determine requirements for HT-UDV measurement of PbLi flows. The HT-UDV system is tested on a PbLi flow driven by a rotating-disk in an inert atmosphere. We find that a sufficient amount of particles contained in the molten PbLi are required to successfully measure PbLi velocity profiles by HT-UDV. An X-ray diffraction analysis is performed to identify those particles in PbLi, and indicates that those particles were made of the lead mono-oxide (PbO). Since the specific densities of PbLi and PbO are close to each other, the PbO particles are expected to be well-dispersed in the bulk of molten PbLi. We conclude that the excellent dispersion of PbO particles enables the HT-UDV to obtain reliable velocity profiles for operation times of around 12 hours.