1104 The aerodynamic characteristics of the baseball ball

Abstract

Wind tunnel experiments were conducted to study the aerodynamic characteristics of the spinning baseball ball 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 ball are studied with the cautions to obtain good linearity 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 tuning technique of dynamic balance. The 3-components aerodynamic forces in the 4-seam arrangements of the axis are reported with the variations of pitching and yawing angles. Ball trajectory calculations were also reported using these aerodynamic characteristics.