Aerodynamic stability enhancement and nonlinear flutter control in piezoelectric integrated bolted multi-plate assemblies under dynamic flow conditions

The current research work focuses on studying the aerodynamic stability and active nonlinear flutter control of a bolted joint multi-panel assembly (BJMP). This structure type, due to its nonlinear aeroelastic properties combined with joint friction and the dynamics of flow, represents a great difficulty for the safety of such a structure. In order to suppress the flutter phenomenon, piezoelectric sensors and actuators are attached to this structure and are shunted with a negative-capacitance piezoelectric shunt damping circuit (NC-PSDC). The complete theory of the BJMP system is formulated, where the contribution of elastic and motional energies of each rim part is included in order to find energy functionals for a hybrid multi-panel assembly using Hamilton’s variational principle. The final eigenvalue problem gives complex eigenvalues; the emergence of flutter is marked by any pair of eigenvalues having positive real parts, thus giving the critical flutter aerodynamic pressure (CFAP) and non-dimensional CFAP (NCFAP). In cases where the critical flutter regime has been exceeded, the non-linear phenomenon is accounted for through a time-stepping approach that involves the combination of Newton’s iteration technique and the Newmark integration technique. The study shows that the NC-PSDC improves aerodynamic stability through a combined mechanism: the shunt modifies the effective electromechanical stiffness of the coupled panel–circuit system, while the resistive branch of the circuit dissipates vibrational energy. The net effect is a substantial reduction of nonlinear flutter oscillations, provided the negative-capacitance ratio is selected below its optimal limit.