Design and Development of Bladeless Vibration-Based Piezoelectric Energy–Harvesting Wind Turbine

Abstract

To meet the growing energy demand and increasing environmental concerns, clean and renewable fluid energy, such as wind and ocean energy, has received considerable attention. This study proposes a bladeless wind energy–harvesting device based vortex-induced vibrations (VIV). The proposed design is mainly composed of a base, a hollow mast, and an elastic rod. The proposed design takes advantage of vortices generated when the airflow interacts with the mast, and the flow splits and then separates and generates vortices that eventually make the elastic rod oscillate, and out of these oscillations, energy can be harvested. Different airflow disruption geometries are studied and tested numerically and experimentally to identify the most effective shape and orientation for converting wind energy to electric energy. Computational fluid dynamics (CFD) modeling and simulations were performed on the elastic mast, a VIV device’s core wind energy–collecting component, to guide the device’s design. These simulations examined the mast-produced lift coefficient, velocity, pressure, and vorticity contours of different mast geometries. The mast’s vibration energy under different wind intensities was also experimentally tested using a scaled model in the wind tunnel. The level of converted electric power was measured and monitored using piezoelectric sensors mounted at different locations on the mast. The experimental study identified the ideal orientation angle of the mast and the best location for the piezoelectric sensors for harnessing more energy. The experiments confirmed the CFD simulation results that a complex cylinder design produces more power. The combined numerical and experimental studies led to an environmentally friendly, new VIV design with much improved power generation capabilities.

Keywords

• wind energy
• energy harvesting device
• vortex-induced vibrations
• computational fluid dynamics