Design and numerical investigation of a multi-directional energy-harvesting device for UUVs

摘要

To supply long-distance and long-term unmanned underwater vehicles (UUVs) with energy, a multidirectional energy-harvesting device for UUVs was designed. The energy-harvesting device can capture energy from multiple directions and from different water currents such as waves and tidal currents by using an oscillating ellipsoidal hydrofoil and a swing arm. The performance of the device was investigated using computational fluid dynamics (CFD) based on the finite volume method (FVM). Two-dimensional unsteady incompressible Navier-Stokes simulations were conducted to investigate the fluid-hydrofoil interaction and determine the energy-harvesting performance. The effects of the geometric parameters, the aspect ratio, swing-arm length, and swing amplitude of the oscillating hydrofoil were systematically studied. The numerical results demonstrated that the geometric shape and aspect ratio of the hydrofoil had significant effects on the energy-harvesting performance of the device; more energy could be extracted at a higher swing amplitude and with the longer swing-arm length. The result demonstrated that the proposed energy-harvesting device has an excellent energy-harvesting performance, and the efficiency could reach up to 31.6%.