Role of Piezoelectric Coupling Factor on FIV-Based Energy Harvesting of a Piezoelectric Flag

The present study investigates the effect of piezoelectric coupling factor of a piezoelectric flag where the energy can be harvested through flow-induced oscillations. The flexible filament structure is placed in an incoming viscous fluid at a low Reynolds number of 200. An in-house immersed boundary method (IBM)-based fluid–structure–energy equations solver has been used for the simulations. It is observed that for a wide range of bending rigidity \(\left( \gamma \right)\) and mass ratio \(\left( \beta \right), \) the dynamics of the flow-induced oscillations are not affected by the piezoelectric coupling factor \(\left( \nu \right). \) However, for a lower \(\gamma\) and \(\beta\) , the oscillation states of the system are significantly affected; for \(\beta = 0.05\) and \(\gamma = 10^{ - 3}\) , the system exhibits self-sustained oscillations at higher ν; otherwise, it was a damped oscillation. In contrast, for higher \(\beta\) values \(\left( {\beta = 5.0} \right)\) , the periodic oscillations of the flexible filament transitions into an aperiodic state in the presence of piezoelectric coupling. The present findings may provide the insights into the design of efficient FIV-based energy harvesting of a piezoelectric flag by identifying the parametric regimes, where the dynamical state is either conducive for energy harvesting or is detrimental.