Measurement of free surface of liquid metal lithium jet for IFMIF target

Kondo, Hiroo*; Kanemura, Takuji*; Yamaoka, Nobuo*; Miyamoto, Seiji*; Ida, Mizuho; Nakamura, Hiroo; Matsushita, Izuru*; Muroga, Takeo*; Horiike, Hiroshi*

Lithium flow experiments were conducted for International Fusion Materials Irradiation Facility (IFMIF) at Osaka University. In the experiment, Li plane jet of 10 mm in depth and 70 mm in width formed by a two contractions nozzle was tested in the velocity range of less than 15 m/s. In the present report, Li surface measurement by pattern projection method was tested. This is a three dimensional image measurement, where stripe patterns are projected onto the flow surface without touching it. The projected patterns were observed to be deformed according to the surface up- and- down. Three-dimensional surface shape could be obtained by analyzing the deformed patterns. By the method, shapes of wave pattern called surface wakes were successfully measured. The surface wakes were observed to be formed from the nozzle edge. It was found that the nozzle edge was damaged and became serrated after lithium flowing of 1,300 hours at this moment.