Numerical analysis of hydroenergy harvesting from vortex-induced vibrations of a cylinder with groove structures

Abstract

The energy generated by vortex-induced vibrations is studied through numerical simulation, and the vibration characteristics of the energy-harvesting device are studied using a bidirectional coupled fluid-structure simulation. The energy collector consists of an elastic cylinder with symmetrical grooves, which can effectively improve the energy extraction performance. The studied range of Reynolds numbers is 15 000 to 100 000 (1.86 <U*water< 11.63). The performance of the energy collector can be significantly affected by modifying various parameters of the grooved structure. Moreover, changing the damping ratio ζn will also affect the energy harvesting. The results show that the grooves affect the dynamic response of the structure; the structure will gallop when the angle between the grooves and the inflow direction is α = 30°. For a grooved cylinder with α = 30° or 60°, the effective power Pharn of the system can be effectively increased, and the grooves can also effectively increase the energy conversion rate ηviv; especially in the case of structure galloping, more energy can be collected, and Pharn and ηviv can be dramatically increased. Immediately after the structure has entered the lock-in region, ηviv reaches its maximum. Varying ζn has little effect on the amplitude of the conductor, but it can effectively enhance energy harvesting and energy conversion.