Validation with the flow properties device of the high-speed fluid in the IFMIF/EVEDA project

Nakaniwa, Koichi; Tanaka, Hiroshi; Ito, Yuzuru; Wakai, Eiichi  ; Yokomine, Takehiko*

In the validation test of the lithium (Li) target system facility under the International Fusion Materials Irradiation Facility/Engineering Validation and Engineering Design Activities (IFMIF/EVEDA), the evaluation test of the flow stability is performed using the 1/2.6 scale in the flow channel of the width of the Li target in the EVEDA Li Test Loop. In this study, to proceed the integrity assessment of the equipment based on the expertise obtained in the validation test of the EVEDA Li test loop, a small water experiment device which is the simulation of the target part, the downstream pipe and the quench tank arranged downstream thereof, or the modification of the flow channel of the downstream pipe, was fabricated. Along with the observation of the high-speed liquid flow by visualization experiments, to confirm the generation conditions of cavitation, an accelerometer was installed in the pipes, and flow properties evaluation was performed with the flow rate, vacuum and temperature as variables. In the observation results, the flow stability in the target up to the speed of 15m/s was confirmed and the spread of the flow in the downstream pipe with the increase in the velocity, was observed. Also, in the evaluation by an accelerometer, at the speed of 8m/s, under the pressure conditions from 20kPa to the atmospheric pressure, the noise values in the downstream pipes are small and the values hardly changed. On the other hand, the noise values were confirmed to increase as the flow velocity increases to 12m/s, 15m/s and vacuum. From now on, the intermittency of the noise phenomena will be examined in detail, and analysis of the flow stability and the optimization of the downstream pipe structure will be examined.