Experimental Investigation of Reynolds Number and Spring Stiffness Effects on Vortex-Induced Vibration Driven Wind Energy Harvesting Triboelectric Nanogenerator

Abstract

Vortex-induced vibration (VIV) is a process that wind energy converts to the mechanical energy of the bluff body. Enhancing VIV to harvest wind energy is a promising method to power wireless sensor nodes in the Internet of Things. In this work, a VIV-driven square cylinder triboelectric nanogenerator (SC-TENG) is proposed to harvest broadband wind energy. The vibration characteristic and output performance are studied experimentally to investigate the effect of the natural frequency by using five different springs in a wide range of stiffnesses (27 N/m < K < 90 N/m). The square cylinder is limited to transverse oscillation and experiments were conducted in the Reynolds regime (3.93 × 103 – 3.25 × 104). The results demonstrate the strong dependency of VIV on natural frequency and lock-in observed in a broad range of spring stiffness. Moreover, the amplitude ratio and range of lock-in region increase by decreasing spring stiffness. On the other hand, the SC-TENG with higher spring stiffness can result in higher output under high wind velocities. These observations suggest employing an adjustable natural frequency system to have optimum energy harvesting in VIV-based SC-TENG in an expanded range of operations.

Flexible Cube-Shaped PTFE-Based Triboelectric Nanogenerator for Improving Wind Energy Harvesting Output

“…The TENG generates electric current through charge transfer when two dissimilar materials come into contact and separate. In general, WD-TENGs would be categorized into three-types: the rotating-disk-based TENG, − flutter-based TENG, − and bead-based TENG (BB-TENG). − The rotating-disk-based TENG encountered stability issues due to wear and tear caused by continuous sliding contact, and the flutter-based TENG was mostly limited to harvesting in the direction of the applied wind and its output saturated at high wind speeds. , The BB-TENG, on the other hand, had the advantage of linear output in multiple directions at high wind speeds . There are typically two types of BB-TENGs based on the voltage output characteristics: a vibration type with linear voltage output and a rotation type with constant voltage output with limited voltage fluctuations.…”

Advancements in Passive Wireless Sensors, Materials, Devices, and Applications

“…An important part of this is how to increase the level of automation at the industrial level. It has become a challenge to achieve a faster and more accurate representation of analogue quantities when reading data [1][2][3]. The rapid development of detection systems in various fields has promoted various sensing technologies, but the layout and deployment of wired sensors have become their main drawbacks, such as power supplies and batteries occupying a large volume of space and the difficulties of post-maintenance management, greatly limiting the performance of sensor systems [4][5][6].…”