1103 Wind tunnel experiment of spinning soccer ball

Abstract

Wind tunnel experiments were conducted to study the aerodynamic characteristics of the spinning soccer balls with variously oriented spinning axes, of which balls are observed in a real game. Ball suspension apparatus with the piano wire strings and a shaft-bearing system through a soccer ball are studied with the cautions to obtain good linearity of spring support, non-interference to the other independent directions and the higher natural frequency of the system. The smooth rotation of a ball was accomplished with well spinning technique of dynamic balance. The 3-components aerodynamic forces of spinning ball in the fundamental arrangement of the axis are reported with the flight path calculations compared with ball flight observation.