title: Velocity field measurement in gas-liquid metal two-phase flow with use of PIV and neutron radiography techniques.
abstract: To establish reasonable safety concepts for the realization of commercial liquid-metal fast breeder reactors, it is indispensable to demonstrate that the release of excessive energy due to re-criticality of molten core could be prevented even if a severe core damage accident took place. Two-phase flow due to the boiling of fuel-steel mixture in the molten core pool has a larger liquid-to-gas density ratio and higher surface tension in comparison with those of ordinary two-phase flows such as air-water flow. In this study, to investigate the effect of the recirculation flow on the bubble behavior, visualization and measurement of nitrogen gas-molten lead bismuth in a rectangular tank was performed by using neutron radiography and particle image velocimetry techniques. Measured flow parameters include flow regime, two-dimensional void distribution, and liquid velocity field in the tank. The present technique is applicable to the measurement of velocity fields and void fraction, and the basic characteristics of gas-liquid metal two-phase mixture were clarified.
authors.affiliation: Research Reactor Institute, Kumatori-cho, Sennan-gun, Kyoto University, Noda, Sennan, Osaka 590-0494, Japan. ysaito@rri.kyoto-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: K
authors.initials: K
authors.lastname: Mishima
authors.forename: Y
authors.initials: Y
authors.lastname: Tobita
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Matsubayashi