White Rose University Consortium logo
University of Leeds logo University of Sheffield logo York University logo

Understanding the effect of seams on the aerodynamics of an association football

Carrè, M. J., Goodwill, S. R. and Haake, S. J. (2005) Understanding the effect of seams on the aerodynamics of an association football. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 219 (7). pp. 657-666. ISSN 0954-4062

Full text available as:
[img] Text
paper_2.pdf

Download (220Kb)

Abstract

The aerodynamic properties of an association football were measured using a wind tunnel arrangement. A third scale model of a generic football (with seams) was used in addition to a 'mini-football'. As the wind speed was increased, the drag coefficient decreased from 0.5 to 0.2, suggesting a transition from laminar to turbulent behaviour in the boundary layer. For spinning footballs, the Magnus effect was observed and it was found that reverse Magnus effects were possible at low Reynolds numbers. Measurements on spinning smooth spheres found that laminar behaviour led to a high drag coefficient for a large range of Reynolds numbers, and Magnus effects were inconsistent, but generally showed reverse Magnus behaviour at high Reynolds number and spin parameter. Trajectory simulations of free kicks demonstrated that a football that is struck in the centre will follow a near straight trajectory, dipping slightly before reaching the goal, whereas a football that is struck off centre will bend before reaching the goal, but will have a significantly longer flight time. The curving kick simulation was repeated for a smooth ball, which resulted in a longer flight time, due to increased drag, and the ball curving in the opposite direction, due to reverse Magnus effects. The presence of seams was found to encourage turbulent behaviour, resulting in reduced drag and more predictable Magnus behaviour for a conventional football, compared with a smooth ball. © IMechE 2005.

Item Type: Article
Copyright, Publisher and Additional Information: Copyright (c) 2005 Professional Engineering Publishing Ltd. This is an author produced version of a paper published in ' Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science`. Uploaded in accordance with the publisher's self-archiving policy.
Keywords: Aerodynamics Drag Football Free kick Lift Magnus effect Smooth sphere Soccer Transition Boundary layers Computer simulation Mathematical models Reynolds number Speed Turbulence Wind effects Wind tunnels Scoccer Wind speed sport wind tunnel modeling
Institution: The University of Sheffield
Academic Units: The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Mechanical Engineering (Sheffield)
Depositing User: Mr Christopher Hardwick
Date Deposited: 20 Aug 2010 15:34
Last Modified: 08 Feb 2013 17:01
Published Version: http://journals.pepublishing.com/content/7l58335q4...
Status: Published
Publisher: Professional Engineering Publishing Ltd
Refereed: Yes
Identification Number: 10.1243/095440605X31463
URI: http://eprints.whiterose.ac.uk/id/eprint/11156

Actions (repository staff only: login required)