Flow measurement of high temperature liquid metal using ultrasonic doppler profiling

Obayashi, Hironari  

Measurement of Lead Bismuth Eutectic (LBE) flow velocity profile was successfully realized in the spallation target model loop of Accelerator Driven System (ADS) by the Ultrasonic Velocity Profiler (UVP) technique. UVP is a powerful tool to measure an instantaneous space-time velocity profile especially on a velocity measurement of an opaque liquid flow, such as liquid metal. We performed velocity measurement along the centerline of the loop and confirmed basic performance of the loop. It was found that there were periodical releases of eddy from the re-circulation region formed near the wall surface of the inner cylinder. We made then a measurement for non-parallel directions with the centerline and observed 3-dimensional structure of LBE flow configuration. On the other hand, there is not the ultrasonic transducer which can apply to high temperature at more than 300 degrees Celsius. Therefore, the development of the high-temperature transducer that can be used at the high temperature condition is a pressing need because it establishes the velocity measurement techniques for LBE flow. Thus we adopted the acoustic wave guide method and conducted a survey of the suitable guide material for LBE flow by using the wave equation.