Inspired by Nature: Efficient Piezoelectric MEMS Actuator Based on Wavelike Excitation

Nature inspires engineers in many respects. Fish locomotion by undulation, e.g., constitutes an optimized technique for transferring momentum from a moving body to a fluid. Considering this fact we conceived a novel integrated, piezoelectric MEMS actuator realized in an aluminum nitride thin-film technology and particularly designed for mimicking this principle. The goal is efficient fluid transport, e.g. for cooling or venting applications. A specifically derived theoretical framework based on numerical simulations, wavelet transforms, and energy balance calculations allows for classifying the generated fluid flow field and for quantifying the transferred local power densities at the fluid-structure interface. This way, the flapper's efficiency w.r.t. volume flow and energy consumption can be assessed allowing for comprehensive comparisons of various designs, excitation waveforms and for setting the benchmark to the natural archetype.