ステレオ画像法による粒子径•速度の同時計測

抄録

A direct-imaging technique for measuring size and velocity of solid/liquid particles dispersed in two-phase flows was developed. The depth-of-focus effect that had imposed a serious limitation on the accuracy of the previous methods was resolved here through the use of a stereoimaging technique. Three-dimensional information provided by stereoimaging has made it possible to obtain simultaneously the size, location and velocity of each particle in the flow. The measurement procedures were fully automated with an on-line system consisting of such devices as two CCD cameras, strobe lamps, and a digital image processor. Particles were identified with a newly devised algorithm which was shown to be robust against the out-of-focus effect. The performance of this algorithm was verified by sizing stationary particles. As a comprehensive test of the present technique, transparent glass beads falling through a vertical pipe were measured.