Aeroelastic Flutter
Definition
A self-reinforcing oscillation in which a structure's motion modifies the aerodynamic forces acting on it in a way that amplifies the motion further, until structural limits are exceeded. Different from resonance, which requires a matching excitation frequency.
- Mechanism
- Structure motion alters aerodynamic force, self-amplifying
- Distinct from
- Resonance, which needs a matching excitation frequency
- Failure mode
- Structural limits exceeded
- Investigated in
- Bridge and aircraft failure analysis
Common questions
How is flutter different from wind-induced resonance in a failure investigation?+
Resonance requires an external forcing frequency matching a structure's natural frequency, while flutter is self-excited: the structure's own deflection changes the aerodynamic load feeding back into further deflection, with no matched external driver needed.
Why is flutter particularly dangerous compared to other vibration failures?+
Because it is self-reinforcing, the oscillation amplitude can grow rapidly once triggered, giving little warning time between the onset of visible motion and structural failure.
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