Modeling an array of surface-piercing piezoelectric plate wave energy converters for wave power absorption

Abstract

In recent years, the pursuit of sustainable ocean energy has accelerated, with wave energy conversion technologies emerging as a promising avenue for low-power electricity generation. Among various approaches, extracting electrical energy from ocean waves through piezoelectric mechanisms offers an innovative and eco-friendly solution. Acting as flexible plate-type wave energy converters, these structures are designed to efficiently capture the hydrodynamic energy of surface waves. The primary motivation behind this work arises from the observation that surface-piercing, vertically oriented piezoelectric plate-type wave energy converters have not been reported in the existing literature, to the best of the authors' knowledge. Despite their significant potential for practical marine energy applications, vertical piezoelectric configurations can provide advantages in achieving the optimum electrical load resistance, thereby maximizing harvested power, compared to horizontally oriented configurations (Kazemi et al., 2021). To overcome the mathematical complexities associated with the coupling between structural flexibility and piezoelectric interactions, a rigorous semi-analytical framework is developed. These complexities arise due to boundary conditions that involve higher-order derivatives with complex-valued coefficients. The governing problem is reformulated into a set of coupled integral equations by employing Green's function solutions along with mixed Fourier transform techniques. These equations are subsequently solved through a Singularity-Respecting Galerkin approximation, yielding accurate evaluations of the hydrodynamic response, including the reflection characteristics, wave power absorption efficiency and hydrodynamic wave forces. Furthermore, a comprehensive parametric investigation is undertaken to elucidate the influences of wave and structural parameters on plate deflection, bending moments and shear forces. Deploying multiple piezoelectric plates in an array has been found to be a more promising approach for wave power absorption. Widening the spacing between adjacent plates greatly influences the deflection of the leeward plate, regardless of whether the edges are clamped-clamped or clamped-free. The outcomes offer valuable physical insights into the energy extraction capability and dynamic behavior of the proposed array of surface-piercing piezoelectric plate-type wave energy converters.