Aeroelastic flutter

Subcritical Hopf bifurcations occur in the dynamics of nerve cells (Rinzel and Ermentrout 1989), in aeroelastic flutter and other vibrations of airplane wings (Dowell and Ilgamova 1988, Thompson and Stewart 1986), and in instabilities of fluid flows (Drazin and Reid 1981). 

Aeroelastic and vibration control technology allows flight vehicles to operate beyond the traditional flutter boundaries, improves ride qualities, and minimizes vibration fatigue damage. Conventional active flutter and vibration control technology relies on the use of aerodynamic control surfaces operated by servo-hydraulic actuators. In this conventional configuration, the... 

The three-dimensional flutter and buffeting problems of flexible bridges have been treated here together in an analytical fashion from a specifically adopted viewpoint the aeroelastic portion is based... 

The approach to bridge aeroelastic stability that concentrates on steady-state and flutter derivatives on the one hand and purely structural dynamics (the determination of eigenmodes) on the other offers an added advantage the two problems are essentially divorced from each other and the aerodynamicist, particularly, is thus freed, in his experiments, from all structural dynamic concerns. 

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