Feb 2005

The flutter of a flag in a gentle breeze, or the flapping of a sail in a rough wind are commonplace and familiar observations of a rich class of problems involving the interaction of fluids and structures, of wide interest and importance in science and engineering. In a recent study, we studied the mechanism that leads to this instability using a combination of analysis and scaling that lead us to a relatively simple theory for the critical velocity for the onset of flutter and the frequency of flapping.

Image courtesy of M. Argentina

Related Media

• “What it takes to get in a flap”, The Guardian, 3 February 2005
• “Kármánsche Wirbelstraßen bringen Fahnen in Schwung”, Die Welt, 14 February 2005

Related Publications