Parametric modeling and experimental characterization of a nonlinear resonant piezoelectric actuator designed for turbulence manipulation

- Novel nonlinear piezoelectric actuator for fast system dynamics.
- High frequency, large amplitude and broad band surface vibrations.
- Single-mode hard duffing-type analytical vibration model.
- Qualitative and quantitative analysis via numerical simulations.
- Successful design integration in the wind tunnel experiments.

In this work we fabricate and optimize a resonant piezoelectric actuator designed for the manipulation of turbulent flow at airfoils and propose analytical expressions for its nonlinear vibration characteristics. High frequency large displacement manipulation of the turbulent boundary layer offers a promising route to influence the frictional drag and hence minimize fuel consumption in modern aviation. Nonlinear design and resonant operation offer a wide-band and energy efficient operation window respectively. The hard duffing-type piezoelectric actuator is designed for extremely fast system dynamics realizing peak-to-peak amplitudes of up to 700 μm in the frequency range of 1100 Hz with a 3 dB operational bandwidth of approximately 100 Hz. A systematic parametric study, based on the derived analytical model, helped to optimize the actuator design. In addition, numerical simulations were performed to analyze the effect of higher order harmonics to a mono-frequency excitation signal. A single degree of freedom duffing-type analytical model was shown to sufficiently predict the nonlinear system dynamics. Furthermore, complete systematic design validation is demonstrated by integration of the resonant actuator in a wind tunnel for a turbulence manipulation study.