A comparison of Jabulani and Brazuca non-spin aerodynamics

Wind-tunnel experimental measurements of drag coefficients for non-spinning Jabulani and Brazuca balls are presented. The Brazuca ball’s critical drag speed is lower than that of the Jabulani ball, and the Brazuca ball’s super-critical drag coefficient is larger than that of the Jabulani ball. Compared to the Jabulani ball, the Brazuca ball suffers less instability due to knuckle-ball effects. Using drag data, numerically determined ball trajectories are created, and it is postulated that although power shots are too similar to note flight differences, goalkeepers are likely to note the differences between Jabulani and Brazuca ball trajectories for intermediate-speed ranges. This latter result may appear in the 2014 World Cup for goalkeepers used to the flight of the ball used in the 2010 World Cup.

[1]  C. B. Daish.  The Physics of Ball Games , 1981 .

[2]  Kazuya Seo,et al.  Factors of unpredictable shots concerning new soccer balls , 2012 .

[3]  Matt Carré,et al.  Soccer ball lift coefficients via trajectory analysis , 2010 .

[4]  R. K. Adair,et al.  The physics of baseball , 1990 .

[5]  Firoz Alam,et al.  Aerodynamics of contemporary FIFA soccer balls , 2011 .

[6]  T. Asai,et al.  Fundamental aerodynamics of the soccer ball , 2007 .

[7]  E. Achenbach,et al.  Experiments on the flow past spheres at very high Reynolds numbers , 1972, Journal of Fluid Mechanics.

[8]  William H. Press,et al.  Numerical Recipes: The Art of Scientific Computing , 1987 .

[9]  F. M. White,et al.  Fluid Mechanics (7th edition in SI Units) , 2011 .

[10]  Simon Choppin.  Calculating football drag profiles from simulated trajectories , 2013 .

[11]  Kazuya Seo,et al.  Characteristics of modern soccer balls , 2012 .

[12]  Firoz Alam,et al.  Effects of surface structure on soccer ball aerodynamics , 2012 .

[13]  Beatriz Defez,et al.  Measurement of Aerodynamic Coefficients of Spherical Objects Using an Electro-optic Device , 2013, IEEE Transactions on Instrumentation and Measurement.

[14]  Firoz Alam,et al.  A Comparative Study of Football Aerodynamics , 2010 .

[15]  E. Achenbach,et al.  The effects of surface roughness and tunnel blockage on the flow past spheres , 1974, Journal of Fluid Mechanics.

[16]  Takeshi Asai,et al.  Flow structure of knuckling effect in footballs , 2011 .

[17]  S. Mitchell,et al.  A mathematical analysis of the motion of an in-flight soccer ball , 2013 .

[18]  J. Goff,et al.  Trajectory analysis of a soccer ball , 2009 .

[19]  John Eric Goff,et al.  A review of recent research into aerodynamics of sport projectiles , 2013 .

[20]  Jörg Franke,et al.  Magnus effect on a rotating soccer ball at high Reynolds numbers , 2014 .