Enhanced performance of piezoaeroelastic energy harvester with rod-shaped attachments

Energy harvesters capture the ambient vibration to persistently drive lower-power devices employed in wireless applications. For enhancing the harvesting performance, a novel piezoelectric aeroelastic (piezoaeroelastic) energy harvester fitted with different rod-shaped attachments is presented. The attachments include square and D-shape rods, and symmetrically fixed on airfoil surface at chord maximum thickness. The performance comparisons of various harvesters are conducted by using simulation and experimental methods. The results demonstrate that square and D-shape rods change flow field characteristic and enhance aerodynamic loads, which reduce flutter velocity and broaden the working bandwidth. The harvesters with square and D-shape rods demonstrate the better output characteristic in both aeroelastic vibration and harvesting performance than without rod. Output voltage of the harvester with square rod is up to 15.14 V at airflow velocity of 16.84 m/s and plunge stiffness coefficient of 278 N/m, and the corresponding output power is 0.765 mW. A maximum enhancement ratio of output power for square rod can reach to 469.7 % at 11.1 m/s. The power density of the harvester with square rod is 4.78 mW/cm³, which demonstrates the superior harvesting performance over others. This work provides a significant guidance for designing the more efficient piezoaeroelastic harvester with square rod.