Analysis and Prediction of Instability Behaviour in Non-Linear Aeroelastic Systems

The effect of non-linearities, be they structural, aerodynamic or control, on the aeroelastic behaviour
of aircraft is becoming of increasing importance in the Aerospace industry. As well as the prediction
of °utter instabilities, there is a need for the prediction and modelling of the onset of Limit Cycle
Oscillations (LCO). A thorough understanding of the possible types of aeroelastic phenomena that
can occur due to non-linearities in the system is required before attempting to predict the behaviour.
In this paper, the onset and suppression of LCOs is investigated by means of an examination of the
stability and energy content of limit cycles.