1993 年 13 巻 Supplement2 号 p. 19-22
The quantitative analysis of a horse-shoe vortex upstream a rectangular plate protuberance standing vertically on a flat ground wall, where the laminar boundary layer develops, was attempted by using a image processing based on spatio-temporal correlation against the visualized particle image. In this image processing method, the velocity vector can be measured by using eight time-lags which are obtained from the time-correlations between a center pixel and each neighboring pixel. This method must employ the time sequential image. But the processing domain for analysis may be smallest among many correlation methods. Therefore, this method was applied to the measurement of velocity and vorticity distributions in the steady flow field which the laminar horse-shoe vortex was formed.