Response of the air flow energy harvester with two side-by-side bluff-bodies of various shapes

The experimental results of flow energy harvesting where the bluff-bodies with different shapes of cross-section are mounted at the ends of the cantilever beams were presented.Namely, bluff-bodies -as cylinders and rectangles -were considered for the interaction with flowing air.The bluff-bodies are coupled through the joint suspension frame where the other cantilever ends were clamped and coupled additionally by vortices created in the space between them.Finally, piezoelectric patches with corresponding electrical circuits were attached to the cantilever beams.They transduce the mechanical energy of the beam-bluff-body resonators into the electrical power.The resulting structure oscillated interacting with the airflow with a range of velocities.High amplitude oscillations caused by the interaction of vortices produced larger voltage response in the electric circuits.As the bluff-bodies of different shapes respond differently, moderate voltage output over a wider velocity range was observed.For illustration of the energy transduction mechanism and qualitative validation of the experimental results, numerical simulations were performed.The differences in the vortex formation and shedding responsible for the vibrations induced in the mechanical structure were shown.