Incorporating PVDF/BaTiO3 piezocomposites with 0–3 and 1–3 connectivity for performance improvement of coupled bending-torsional vibration energy harvesters

Abstract

This study investigates the performance enhancement of coupled bending-torsional (BT) vibration energy harvesters (VEHs) by incorporating polyvinylidene fluoride (PVDF)/barium titanate (BaTiO3) piezocomposite layers. A unimorph cantilever beam, subjected to BT vibrations, is analyzed using finite element (FE) modeling to evaluate the impact of BaTiO3 (BTO) fiber orientation and connectivity patterns (0–3 and 1–3) within a PVDF matrix. The influence of fiber orientation on the electromechanical properties of long-fiber piezocomposites (LFPs) and short-fiber piezocomposites (SFPs), as well as their corresponding voltage and power output for BT-piezoelectric vibration energy harvesters (PVEHs), has been numerically investigated. Optimal performance for XZ-piezocomposites with 1–3 connectivity (LFPs) is observed at an off-axis angle of 70˚, yielding average maximum voltages of 7.24 V and power of 26.39 μW across the first two vibration modes. For 0–3 connectivity (SFPs), optimal performance occurs at a 50˚ off-axis angle. Furthermore, increasing the mass ratio enhances the contribution of the second vibration mode, potentially broadening the effective frequency range of the harvester. These findings offer crucial insights for optimizing piezocomposite design in energy harvesting applications, particularly for BT-VEHs. © 2025 Taylor & Francis Group, LLC.