Numerical Study of Wake-Induced Vibration on a Square Prism with Splitter Plate, placed downstream of a Larger Circular Cylinder for Piezoelectric Energy Harvesting Applications

Abstract

Flow-induced vibration for energy harvesting is a developing technology, especially at low velocity and small dimensional regimes where conventional turbines are found ineffective. This study numerically explores the wake-induced vibration and interference between galloping and vortex-induced vibration phenomenon on a square prism (12mm) with a splitter plate (60mm length) setup that is placed downstream of another larger circular cylinder (40mm) for piezoelectric energy harvesting applications. Introducing an upstream cylinder created oscillating vortices on the downstream square prism that would otherwise have non-oscillating lift and drag forces. Distance between the bluff bodies was studied at 5D and 3D, D being the diameter of circular cylinder at 4 m/s velocity, and sinusoidal coefficient of lifts with maximum values of 0.85 and 0.98 respectively were obtained. Using splitter plate, the coefficient of lift increased drastically to 2.3 from 0.9. CFD simulation was run from 0.5 m/s to 10 m/s. As the velocity increases, coefficient of lift as well as the vortex shedding frequency increases reaching the maximum of 4.6 and 43.33 Hz at 7 m/