Complexity Digest 2007.20 - 15
Bat Flight Generates Complex Aerodynamic Tracks, Science
Excerpts: The flapping flight of animals generates an aerodynamic footprint as a time-varying vortex wake in which the rate of momentum change represents the aerodynamic force. We showed that the wakes of a small bat species differ from those of birds in some important respects. In our bats, each wing generated its own vortex loop. Also, at moderate and high flight speeds, the circulation on the outer (hand) wing and the arm wing differed in sign during the upstroke, resulting in negative lift on the hand wing and positive lift on the arm wing.
- Source: Bat Flight Generates Complex Aerodynamic Tracks
[ http://www.sciencemag.org/cgi/content/full/316/5826/894 ], A. Hedenstr?m, L. C. Johansson, M. Wolf, R. von Busse, Y. Winter, G. R. Spedding, Science : 894-897., 07/05/11