Abstract
It is said that the cause of the swerving ball on no rotating shoot of the soccer ball depends on the outbreak of the vortex occurred in the wake. However, it is not grasped the timing among the vortex outbreak and the swerving of balls. In this study, the velocity fluctuation of the ball wake was measured with hot wire probe and the oscillation of the ball was measured with three components load cell. Those experimental results were analyzed by wavelet transform and a relations among the velocity fluctuation and the fluid forces was grasped experimentally.
