Piezoaeroelastic system on the basis of a double aerodynamic pendulum

During last decades, possibilities to use piezoelectric generators to harvest energy from the flow-induced vibrations of different structures are intensively studied. In particular, various wind power harvesters based on fluttering oscillations of wing sections are proposed. In this work, an electromechanical system is considered that consists of a double aerodynamic pendulum connected with a piezoelectric element in such a way that rotation of the first link of the pendulum results in deformation of the piezoelement. The element is connected to a load resistance. Stability of the trivial equilibrium is analyzed, and conditions for stability loss are discussed. It is shown, in particular, that it is possible to choose parameters of the system in such a way that the trivial equilibrium (where both links of the pendulum are oriented along the incoming flow) is unstable when the wind speed belongs to a certain finite range of values, and asymptotically stable outside this range. Periodic solutions of the system are studied numerically depending on the wind speed and the moment of inertia of the second pendulum link. The effect of disappearance of limit cycles in the range of large wind speeds is demonstrated.