Numerical investigation on a novel VIV energy harvester for underwater mooring platforms

Inspired by the wave roller device and the artificial piezoelectric grass energy collection devices which harvest energy from wave and air respectively, a novel flow-induced vibration energy converter (FIVEC) was proposed to convert fluid kinematic energy into electricity for underwater mooring platforms (UMPs) and extend their operation time. The FIVEC intends to be fixed on the sea bed or other underwater structures, and is composed of a vibrating thin plate, magnetic couplings (MCs) and several generators. The plate's driving torque which is resulted from shedding vortices' kinematic energy, is transmitted to generators through MC to produce electricity. In order to quantify and evaluate performances of the FIVEC, two-dimension computational fluid dynamic (CFD) simulations were performed. The adopted CFD method was firstly validated using existing experimental data. Under different damping coefficients and current velocities, the responses of the plate's angular displacement amplitude and the power performances of the converter were studied. Results show that the device has a maximum averaged efficiency of 3.5% (147mW) in prescribed situations, which demonstrates the feasibility of this energy converter. This article also provides guidance for the follow-up test.