Von Kármán vortex street

A Von Kármán vortex street is a repeating pattern of swirling vortices. It is named after Theodore von Kármán.

The vortices are formed as pressure differences, created by the obstacle, force some of the air (or fluid) to move more quickly than the rest.

Recent studies show that insects borrow energy from the vortices that form around their wings during flight. Normally vortices just create drag. But insects can recapture some of their energy and use it to improve speed and maneuverability. Insects learn to rotate their wings before starting the return stroke, and the wings are lifted by the eddies of air created on the downstroke.

External links

• Atmospheric Vortices near Guadalupe Island
• Von Kármán vortex street animation and explanation.
• Vortex streets and Strouhal instability