A study of double flutter

We study nonlinear flutter phenomena in a system of two airfoils in close proximity in an ideal fluid. In particular, we are interested in cases for which two aeroelastic instabilities are nearly critical simultaneously. Such Hopf-Hopf interactions, in general, are capable of generating a rich variety of dynamic phenomena, behaviors that possibly can be exploited to develop flow actuators. Our first task is to investigate the degree to which the double Hopf interactions are prevalent in the physical system. Secondly, using tools of center manifolds and normal forms, we investigate the richness of the dynamics in the two airfoil system. Analysis is facilitated by an effective reduced-order modeling effort. (C) 2004 Published by Elsevier Ltd.