抄録
For making clear the phenomena on the unsteady heat transfer with liquid film in two phase flow, the measurements are needed about unsteady film thickness and velocity profiles in the liquid film adding time-averaged values. It would be very important especially to estimate the dry out mechanism of liquid film experimentally on fuel rod around the spacer in the new fuel assembly of BWR. In this study, the unsteady velocity profiles would be estimated by the surface velocity profiles, which were detected experimentally by the tracking of the visualizing particles with image processing. As the particles were impacted and moving on the surface with transferring the properties with diffusions, the time-special tracking with various methods indicate the position of impacts and flows on the surface, which give the useful information about liquid film.
