Visualization of dolphin-kicking wake using 3C-PIV method

Introduction Swimming is the movement through water by moving the body or parts of body. We can propel the body by stroking and kicking motion. Many researches which had tried to determine the propulsive force have been reported. Most of these estimations were based on quasi-steady analysis. However, the flow field around human body during swimming is the very unsteady situation. There had been no technique for analyzing under unsteady condition in swimming. Therefore, no research based on unsteady flow theory has been reported. Recently, a new analytical method for unsteady condition called Particle Image Velocimetry (PIV) was developed. We have applied this method to swimming analysis (Miwa, T. et al. 2004, Matsuuchi, K. et al. 2004) and been trying to improve it. The present aim of this study was to visualize and to analyze the unsteady flow field of the wake of dolphin kicking motion using 3-component PIV method.