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

摘要

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 zeta(n) 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 alpha = 30 degrees. For a grooved cylinder with alpha = 30 degrees or 60 degrees, the effective power P-harn of the system can be effectively increased, and the grooves can also effectively increase the energy conversion rate eta(viv); especially in the case of structure galloping, more energy can be collected, and P-harn and eta(viv) can be dramatically increased. Immediately after the structure has entered the lock-in region, eta(viv) reaches its maximum. Varying zeta(n) has little effect on the amplitude of the conductor, but it can effectively enhance energy harvesting and energy conversion.