2013 Fiscal Year Final Research Report
Research and development of a tracking type airflow visualisation system
Project/Area Number |
23650381
|
Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Multi-year Fund |
Research Field |
Sports science
|
Research Institution | University of Tsukuba |
Principal Investigator |
ASAI Takeshi 筑波大学, 体育系, 教授 (00167868)
|
Co-Investigator(Kenkyū-buntansha) |
KOIKE Sekiya 筑波大学, 体育系, 准教授 (50272670)
|
Project Period (FY) |
2011 – 2013
|
Keywords | スポーツ / 流体 / サッカー / ボール / 可視化 / 渦 / 揚力 / 抗力 |
Research Abstract |
A thin smoking agent was applied to a soccer ball to make the vortex flow around the ball in actual flight visible, and images were captured from behind by using a high-speed video camera (1,000 fps). Two-dimensional vector diagrams depicting slipstreams of the ball featured a phase in which a pair of vortices were observed as large-scale vortex structures, as well as a phase in which the large-scale vortex structure was unclear. Based on an analogy between wingtip vortices and the large-scale structures of these vortices, a lift force related to downwash was speculated to have occurred. The lift force due to such a large-scale vortex pair structure can at times slowly rotate the ball, whose major axis is in the direction of movement, in the axial direction. This was considered to be a potential cause for the slight wobbling of the ball.
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Research Products
(9 results)