Aerodynamics of Used Cricket Balls

A cricket ball possesses six rows of stitches with approximately 70 to 90 stretches in each row and a prominent seam at the joining of two halves. Asymmetric airflow over the ball due to seam orientation and surface roughness of the ball can cause the flight deviation (swing) and unpredictable flight. Swing makes difficult for the batsman to hit the ball with the bat and guard the stamps. The primary objectives of this work were to understand the aerodynamic properties of a series of used cricket balls, thus the mechanism of swing as well as drag of a cricket ball. The aerodynamic forces and moments of used and new balls were measured under a range of speeds at various seam orientations. The airflow around the balls was visualized and documented. The preliminary data analysis indicated that the wear & tear and seam angle have significant effect on aerodynamic drag and side forces of the cricket ball.