Three dimensional LES simulation of bi-directional turbine for wave energy conversion

Development of technology to harness the vast amount of renewable energy available in nature has been ever-increasing in popularity. A worldwide desire to limit dependency on fossil fuels as a means to produce power has motivated research in solar, wind, and wave energies, as well as other clean, naturally-abundant energy sources. This research details an innovative design for a wave energy harvester that converts the heaving motion of waves into electrical power. The conceptual design utilizes a unique bidirectional turbine system that develops torque in a single direction, independent of whether the fluid is moving upward or downward. The result is power production both as the buoy is heaved upward by a wave as well as while the buoy falls after the wave passes. A transient three dimensional LES turbulent CFD model of the bi-directional turbine system is modeled in OpenFoam. A dynamic boundary is introduced in order to model the transitional period in which water flow changes direction within the bi-directional turbine channel. The analysis of the simulation will conclude in an optimized load control algorithm which can adapt the generator load to increase the systems efficiency during the flow transitional period.