Optimal Design Guidelines for Efficient Energy Harvesting in Piezoelectric Bladeless Wind Turbines

This study presents an optimal design methodology for a piezoelectric-based bladeless wind turbine (BWT) that efficiently converts wind-induced vibration of a cantilever-mounted cylinder into electrical energy. A lumped-parameter model integrating structural dynamics, fluid-structure interaction, and piezoelectric energy conversion is introduced and simplified to derive key dimensionless design parameters and optimal conditions for maximizing power output. The optimal design criteria are as follows: tuning the resonance between the structural natural frequency and vortex shedding frequency; setting the dimensionless load resistance R* to unity; and minimizing ωnRLCeq to a value smaller than unity. Numerical simulations and wind tunnel experiments validate the model, showing good agreement with less than 7% error in power prediction under resonance conditions and successfully predicting the coupled behavior of fluid, structure, and piezoelectric components. The proposed optimal design methodology facilitates the development of compact and efficient piezoelectric-based bladeless wind energy harvesting systems suitable for urban and space-constrained environments.