Dynamic analysis of nonlinear aeroservoelasticity by a modified frequency-time domain method

ifasd2024 Tracking Number 45

Dynamic analysis of nonlinear aeroservoelastic systems has been a subject of concern for decades. A modified frequency–time domain method is competent in analyzing nonlinear aeroelastic systems, with the capability of addressing various nonlinearities and initial conditions. An extension of this method is presented to allow nonlinear responses of closed-loop systems with freeplay and actuator nonlinearities. Aeroservoelastic systems can be reconstructed by extracting nonlinear elements as pseudo forces in the nonlinear feedback loops in the time domain, whereas the original feedback loops are also introduced via the convolution integral. Hence, nonlinear responses with various nonlinearities and initial conditions can be obtained by the proposed method. Numerical results are provided for a three-degree-of-freedom airfoil section with freeplay and actuator nonlinearities, which is augmented to an aeroservoelastic system. Compared with the Runge–Kutta algorithm, the feasibility and accuracy of the proposed method can be validated. As an alternative to time-marching approaches, the modified frequency–time domain method initiates a novel process to address various nonlinearities and initial conditions in nonlinear aeroservoelastic systems.