Design and Optimization of Laminated Piezoelectric Honeycomb Beams with CFRP and Nanocomposite Face Sheets for Enhanced Vibration Energy Harvesting

Efficient vibration energy harvesting is crucial for powering self-sustainable sensors and devices in remote and low-power applications. Honeycomb beam structures provide enhanced dynamic response and lightweight design, but existing research primarily focuses on metallic and polymeric cores, with limited exploration of advanced composite configurations. This study addresses this gap by investigating the vibration energy harvesting performance of laminated piezoelectric honeycomb beams (LPHBs) with a honeycomb core layer and advanced composite face sheets made of carbon fiber reinforced polymer (CFRP), CFRP reinforced with multi-walled carbon nanotubes (MWCNT), and fiber-metal laminates (FML). A comprehensive numerical framework is developed to evaluate the influence of composite face sheets, honeycomb geometry (cell angle, cell thickness, and height-to-length ratio), and nanofiller reinforcement on the natural frequency, vibration amplitude, and average output power of the harvester. The results reveal that CFRP face sheets deliver high stiffness-to-weight efficiency, while MWCNT-reinforced CFRP enhances electromechanical coupling and increases power output by up to 20% compared to pure CFRP. The FML-based honeycomb configuration shows superior durability and improved damping, yielding stable energy harvesting performance over a wide frequency band. To further maximize performance, a surrogate model-assisted improved particle swarm optimization (IPSO) approach is employed, identifying an optimal combination of material and geometric parameters that enhance the output power by over 25% compared to baseline designs. The findings demonstrate the potential of CFRP, CFRP-MWCNT, and FML face-sheet integrated honeycomb beams for lightweight, efficient, and tunable vibration energy harvesters, with promising applications in structural health monitoring, wireless sensor networks, and self-powered portable electronics.