Flow-induced vibration of inherently nonlinear structures with applications in energy harvesting

Abstract

This paper proposes a novel design for a flow-induced vibration-based energy harvester, consisting of an elastic L-shaped beam, with an inherent nonlinearity in its structural stiffness as an alternative to the classical cantilever beam used in conventional fluidic energy harvester designs. The L-shaped beam supports a prism at its tip and undergoes large-amplitude galloping oscillations. The results from wind tunnel experiments show that by replacing a conventional linear structure that supports the prism with a nonlinear one, the high frequency flow components, shed from the tip prism, were capable of exciting the oscillations of the structure at higher harmonics of the main resonance, thus enhancing the power density of the energy harvester. As a result of improved power density values, the proposed harvester design holds great potential to be used as advanced space-efficient energy harvesters.