A Comparative Study of Baseball and Softball Aerodynamics

摘要: The baseball and softball games are popular sports in American continent as well as some other parts of the world. In both games, spherical balls are used. The flight trajectory of a baseball and softball largely depends on its aerodynamic characteristics. Despite the popularity of the game, it appears that scant information on the aerodynamic force experienced by a baseball and softball is available in the open literature. Having over 108 curved stitches, complex seams and their orientation, the airflow around a baseball is believed to be significantly complex and little understood. The primary objectives of this study were to evaluate aerodynamic parameters of several commercially manufactured baseballs and softballs. The aerodynamic forces and moments were measured experimentally. The aerodynamic forces and their non-dimensional coefficients were analysed. The results indicate that the drag coefficient of a base ball is close to other closely related balls such cricket ball. The result also indicates that there is a variation in drag coefficients between a baseball and a soft ball. The findings also indicate that the seam orientation has profound impact on ball’s aerodynamic characteristics.