Energy harvesting from flow-induced acoustic pressure using parallel piezoelectric plates with nonlinear fluid coupling

The role of fluid acoustic pressure has been extensively explored in the context of fluid–structure interaction (FSI); however, its potential for energy harvesting remains largely underutilized. This paper proposes a novel design for energy harvesting from flow-induced acoustic pressure using parallel piezoelectric plates. The study presents a method in which acoustic pressure is confined between stacked plates and harnessed by piezoelectric patches. The nonlinear coupling induced by the acoustic medium is analytically modeled, and the governing equations are derived using Hamilton's principle. A semi-analytical approach is employed, combining the differential quadrature method (DQM) and Galerkin's method to predict the system's steady-state response under harmonic excitation. The model is validated through comparison with prior studies, demonstrating strong agreement. The system's performance is evaluated by varying the number of plates, pitch height, aspect ratio, electric conductance, and mean flow channel velocity. The results indicate that tuning the dimensionless mean flow channel velocity significantly enhances both the frequency bandwidth and output voltage, optimizing the system for more efficient energy harvesting. This work provides valuable insights into the potential for utilizing fluid acoustic pressure for sustainable energy harvesting.