05 January 2012
New paper about aerodynamics in slow-flying flycatcher
Just of the press from the Journal of the Royal Society Interface is a paper about pied flycatcher aerodynamics, by aouthors Florian Muijres, Melissa Bowlin, Christoffer Johansson and Anders Hedenström. Stereo flow-visualization was used to study the wake vortices shed off the wings of flycatchers as they flew slowly in the wind tunnel. The results sow that the aerodynamic force is mainly from the downstroke, resulting in a closed vortex loop. The results also show that the tail is involved in deflecting the downwash, resulting in an aerodynamic efficiency comparable to that of cruising flight. During the upstroke the wings generate no significant forces, but the body-tail configuration does to some degree, and so the upstroke phase of slow flight is not completely uninteresting from an aerodynamics viewpoint.