Performance Investigation of a Flexible Polyvinylidene Fluoride (PVDF) Energy Harvester Array in a Two-Stage Vertical...

The performance characteristics of wind-induced energy harvesting were experimentally investigated using a flexible polyvinylidene fluoride (PVDF) energy harvester with a two-stage, parallel, and vertically aligned configuration. Ten PVDF film modules were serially connected to form a single set, and four identical sets were assembled into three different array configurations-2 × 2, 4 × 1, and 1 × 4-to systematically examine the effects of array geometry and vortex interaction on power generation performance. Experiments were conducted at wind speeds ranging from 1 to 3 m/s. At a wind speed of 3 m/s, the 2 × 2 array configuration achieved an average charging voltage of 2.895 V and a total output power of 0.731 W after 600 s, corresponding to approximately 3.3-fold and 4.2-fold increases, respectively, compared with those of the 4 × 1 (0.224 W) and 1 × 4 (0.176 W) configurations. Furthermore, the uniformity index (U = 0.701), vortex amplification index (G = 0.663), and array efficiency (η = 0.789) demonstrate that the 2 × 2 configuration provides the most uniform and efficient energy distribution among the tested configurations. These results indicate that the proposed two-stage parallel funnel-type PVDF energy harvester with a 2 × 2 array configuration is an effective design for high-efficiency energy harvesting, even under low wind speed conditions.