Abstract
This research investigates the potential of clean energy harvesting using Sliding-Mode Triboelectric Nanogenerators (S-TENGs) to convert energy from Flow-Induced Vibrations (FIV) into usable electrical energy. Triboelectric Nanogenerators have been integrated into various applications such as fabrics, jewelry, and micro-sensors. The primary focus of this study is to use S-TENGs in Fluid-Structure Interactions (FSI) to harvest energy from FIV by utilizing the response from FSI to initiate motion between the S-TENG plates. Considering their compatibility with easily obtainable materials, cost-effective manufacturing, and adaptability for various applications, S-TENGs may be the next step in clean energy harvesting techniques. Traditional energy harvesting methods for S-TENGs have been predominantly mechanical, employing actuators and motors to move the electrodes. However, by incorporating fluid flow, it is now possible to harvest electrical energy from a flowing fluid, converting the original energy source into a renewable one. The FIV-based energy extraction process involves a flexibly mounted solid, triangular cylinder placed in a flowing fluid that undergoes large-amplitude flow-induced vibration. But what is the flow-induced vibration? When a flowing fluid interacts with a stationary or moving bluff body, a vortex dominated wake is formed behind it. If the structure is flexible, or flexibly-mounted, the vortex shedding in the wake of the bluff body can lead to galloping—an FIV instability observed in bluff bodies with large oscillation amplitudes normal to the flow direction at low frequencies. Here in this research, the benefits of TENGs operating at low frequencies, such as those observed in the galloping type FIV response of the triangular structure, were examined in detail. Our results indicate that by adjusting the flow velocity, contact pressure, and resistance in the electrical circuit, the FIV response can be altered, directly affecting the energy harvesting efficiency. Our results also show that an S-TENG operating under constant contact pressure exhibits different behavior when the flow velocity and circuit resistance are varied. By changing the resistance and velocity, there is an optimum efficiency and power for which this system best operates. These results demonstrate the potential of S-TENGs to produce usable, efficient power when set at their optimum resistance, offering a promising foundation for developing large-scale S-TENG energy harvesters capable of generating clean, renewable energy with minimal environmental impact.