Energy Transformation Mechanism of Coupled Bendingtorsional Flutter

Abstract:

The method of coupled flutter energy analysis is proposed on the basis of the incentivefeedback mechanism and the energy stability criterion for flutter is also defined.System energy change regularity of structureair system under flutter critical wind speed is analyzed according to plate wind tunnel test.The results show that the transfer channel of the energy from the vertical degree of freedom to torsional degree of freedom is built by the aerodynamic derivatives of A*1H*3,which cause a large amount of energy accumulation in the torsional degree of freedom,and ultimately beyond the energy dissipation capacity of aerodynamic damping,resulting in the loss of torsional vibration stability of the flutter instability patterns.The research finds that A*1H*3 cos θ1 has great influence on the main energy source of system torsional motion.The main energy expenditure is torsional aerodynamic damp and the expenditure of mechanical damp is less.Inertia force,elastic force and aerodynamic stiffness of torsional system are all have no energy expenditure in oneperiod.