https://pure.hw.ac.uk/ws/files/34728103/ECM_2020_hybrid_VIV_gallop.pdf

Hybrid wind energy scavenging by coupling vortex-induced vibrations and galloping

Flow-induced vibration of a circular cylinder with splitter plates placed upstream and downstream individually and simultaneously

A hybrid piezo-dielectric wind energy harvester for high-performance vortex-induced vibration energy harvesting

Galloping based piezoelectric energy harvester is a kind of micro-environmental energy harvesting device based on flow-induced vibrations. A novel tristable galloping-based piezoelectric energy harvester is constructed by introducing a nonlinear magnetic force on the traditional galloping-based piezoelectric energy harvester. Based on Euler–Bernoulli beam theory and Kirchhoff’s law, the corresponding aero-electromechanical model is proposed and validated by a series of wind tunnel experiments. The parametric study is performed to analyse the response of the tristable galloping-based piezoelectric energy harvester. Numerical results show that comparing with the galloping-based piezoelectric energy harvester, the mechanism of the tristable galloping-based piezoelectric energy harvester is more complex. With the increase of a wind speed, the vibration of the bluff body passes through three branches: intra-well oscillations, chaotic oscillations, and inter-well oscillations. The threshold wind speed of the presented harvester for efficiently harvesting energy is 1.0 m/s, which is decreased by 33% compared with the galloping-based piezoelectric energy harvester. The maximum output power of the presented harvester is 0.73 mW at 7.0 m/s wind speed, which is increased by 35.3%. Compared with the traditional galloping-based piezoelectric energy harvester, the presented tristable galloping-based piezoelectric energy harvester has a better energy harvesting performance from flow-induced vibrations.

Design, modeling and experiments of broadband tristable galloping piezoelectric energy harvester

A mini review of recent progress on vortex-induced vibrations of marine risers

Two-degree-of-freedom flow-induced vibration of a rotating circular cylinder

The flow-induced vibration (FIV) of multiple cylinders is a common phenomenon in industry and nature. The FIV and energy harvesting of three circular cylinders in tandem are numerically studied by 2D-URANS simulations in Reynolds number range of 30,000 < Re < 105,000. Simulation results match well with experiments in the tested cases. Four branches of FIV are clearly captured in the amplitude and frequency ratio curves of the three cylinders with roughness, including initial branch of vortex-induced vibration (VIV), VIV upper branch, transition from VIV to galloping, and galloping. It is shown that the vortices from downstream cylinder are strongly disrupted and modified by vortices of upstream cylinder. The third cylinder is almost suppressed in VIV initial branch. The 2P vortex pattern is observed for the first cylinder in the VIV upper branch. For Re = 90,000 in the transition regime, the vortex patterns of the first and second cylinders are 2P + 4S and 2P + 2S, respectively. In the galloping branch, the shear layer motion is in synchronization with the motion of the cylinder, and the maximum amplitude of 2.8D is reached by the first cylinder. The total converted power of the three cylinders increases with U*water both in the simulation and experiment. For the three cylinders, the maximum power reaches up to 85.26 W with the increase of Reynolds number. The energy conversion efficiency is stable and higher than 35% in the starting region of VIV upper branch, and the maximum value of 40.41% is obtained when Re = 40,000.

Research on Flow-Induced Vibration and Energy Harvesting of Three Circular Cylinders with Roughness Strips in Tandem

Control of two-degree-of-freedom vortex-induced vibrations of a circular cylinder using a pair of synthetic jets at low Reynolds number: Influence of position angle and momentum coefficient

Control of two-degree-of-freedom vortex induced vibrations of a circular cylinder using synthetic Jets: Effect of synthetic jet orientation angle and phase difference

Qunfeng Zou

Papers

Two-degree-of-freedom flow-induced vibration of a rotating circular cylinder

Research on Flow-Induced Vibration and Energy Harvesting of Three Circular Cylinders with Roughness Strips in Tandem

Control of two-degree-of-freedom vortex-induced vibrations of a circular cylinder using a pair of synthetic jets at low Reynolds number: Influence of position angle and momentum coefficient

Control of two-degree-of-freedom vortex induced vibrations of a circular cylinder using synthetic Jets: Effect of synthetic jet orientation angle and phase difference

Two-degree-of-freedom flow-induced vibration of two circular cylinders with constraint for different arrangements