Little Eddies and Small Vibrations: Untapped Sources for Energy Harvesting in Aquatic Environments

New York University, New York NY

Investigators

Abstract

This research program addresses the grand challenge of extracting usable energy from small-scale aquatic systems. This program envisions establishing a fundamental understanding of the spectrum of energy scavenging modalities in marine environments towards the development of self-sustained multifunctional marine microsensors. This project seeks to exploit ambient mechanical vibrations and coherent fluid flow structures for energy harvesting. Mechanical vibrations in aquatic environments occur in a vast array of both man-made and natural structures, as well as in animal swimming. Coherent fluid structures, such as Karman vortex streets and turbulent eddies, are generally present in aquatic environments and are due to a variety of mechanisms, including flow separation from fixed immersed bodies, thermal and pressure gradients, and momentum transfer from swimming animals. Practicality dictates that harvesters for underwater applications be lightweight, require small forces and low frequencies to elicit motion, produce sufficient electrical power to run a set of microdevices, and operate in wet conditions. Ionic Polymer Metal Composites (IPMCs) meet all of these requirements and are thus selected for this study.