Ocean Wave Energy Capture Through Ferrofluid Sloshing

Abstract

Ocean surface waves carry vast amounts of energy that could be harnessed as a renewable source of electricity generation. However, current ocean energy capture devices fail to be economically viable due to large costs associated with the installation and maintenance of mechanical components in the harsh ocean environment. We propose a device that harvests ocean wave energy via the sloshing of a ferrofluid in a magnetic field, thus removing the need for expensive and complex mechanical linkages from the energy capture scheme. An analysis is conducted of the governing equations for the sloshing of a ferrofluid in an unsteady rotating reference frame when a uniform magnetic field is present. The ferrofluid energy capture concept is then validated in experiment and it is shown that a prototype device is capable of generating voltages in the range of 0.4-1.75mV when subjected to unsteady rotations of varying amplitudes and frequencies. The role of resonance in the slosh dynamics is briefly discussed, and the feasibility of the device for use powering ocean sensing systems is established.