Developing a Hydropower Vortex Induced Vibration System in Slow Stream Water

Abstract

Energy resources are beginning to replenish and the reliability on renewable energy has increased to 30% as we approach year 2020. However the current sources of renewable energy used for mass generation also have its own drawbacks mainly in terms of costing, maintenance and geographical changes which incur environmental disturbances. Energy harvested from Vortex Induced Vibrations (VIV) in water with a continuous flow of more than 0.3m/s has the ability to replace conventional hydropower methods with a more cost efficient and environmental friendly way. This research managed to produce a prototype focused on using a spring system to maximize oscillations induced by the vortex in flowing water onto a cylinder shaped PVC pipe of a specific diameter. The energy harvesting method adapted in this system is a piezoelectric tape. Upon every oscillation, the designed system is able to flick the piezoelectric tape inducing a certain amount of voltage. Initial design of prototype was to discover the most adequate cylinder PVC pipe for vortex in water to produce oscillations. The best way to design the system was tested to maximize flow induced oscillations. The final prototype of this stage also found the best harvesting method for the transformation process of induced oscillation into electrical energy. At this stage the prototyping is detailed at combining the existing prototype and piezoelectric transducers. The end product successfully produced up to 0.2watts/second of power. However, the unstable flow conditions and small scale testing prototype incurred an inconsistent power generation. From this research, it was brought to conclusion that the prototype has to be of a larger scale for real life applications of vortex induced vibration hydropower system.