US Air Force Academy, Air Force Link, August 20, 2008
The National Science Foundation has awarded the Academy’s Aeronautics Department $285,619 to support a cyclodial propeller wave energy converter research project to harness the ocean’s power.
The concept of ocean waves turning power-generating turbines is simple — put propellers underwater, then let the motion of incoming and outgoing waves, along with tidal currents turn the propellers and turbines to crank out electricity. But making those turbines efficient, effective and survivable in both shallow and deep water is what has prevented large-scale application in harnessing wave energy.
But the Academy’s Aeronautics Department might be able to solve these problems. Years of research on military aircraft have given Aeronautics researchers the rare and necessary expertise in feedback flow control and fluid dynamics to potentially harness wave energy to meet the nation’s growing power needs.
The Aeronautics Department will partner with Oregon State University to use their wave tunnel for some of the experimental side of this research project. Through both computational and experimental research, the Academy will pursue development of a wave energy converter based on cycloidal propellers, like those used on tug boats. These propellers’ main advantage is the ability to produce thrust in any direction perpendicular to the propeller shaft.
This project investigates the use of cycloidal propellers for energy extraction from unsteady flow fields created by both deep and shallow water waves. Both of the three-dimensional flows are a challenge to energy conversion devices since they provide a flow field that fluctuates in time.
Historically, wave energy converters have some drawbacks, one being the need for some kind of mooring to the ocean floor, which increases the cost of the device, as well as susceptibility to damage from storms. The cycloidal propeller based wave energy converters investigated in this project has the potential to overcome this and other problems of conventional wave energy converters, such as scalability to large power levels and efficiency of energy conversion.
“Wave power has the potential to provide a large portion of the world’s electric energy needs, if it can be tapped in an efficient way,” said Dr. Stefan Siegel, who will oversee this research project.
Cadets will also catch this wave, performing the basic research as part of the Aeronautics 471 class during their senior year.
This project, which is funded through 2011, is part of a broader Air Force effort to address energy related issues and to support renewable alternative energies research.