Shown is the view from the far downstream end into the test section of the U.S. Air Force Academy water tunnel. Three blades of the cycloidal turbine are visible at the far end. Engineer Stefan Siegel and his colleagues test the turbine using the tunnel, with both steady and oscillating flow conditions simulating a shallow-water wave-flow field. (Credit: SSgt Danny Washburn, U.S. Air Force Academy, Department of Aeronautics)

ScienceDaily (Nov. 20, 2009) — The ocean is a potentially vast source of electric power, yet as engineers test new technologies for capturing it, the devices are plagued by battering storms, limited efficiency, and the need to be tethered to the seafloor.

Now, a team of aerospace engineers is applying the principles that keep airplanes aloft to create a new wave-energy system that is durable, extremely efficient, and can be placed anywhere in the ocean, regardless of depth.

While still in early design stages, computer and scale-model tests of the system suggest higher efficiencies than wind turbines. The system is designed to effectively cancel incoming waves, capturing their energy while flattening them out, providing an added application as a storm-wave breaker.

The researchers, from the U.S. Air Force Academy, will present their design at the 62nd annual meeting of the American Physical Society's Division of Fluid Dynamics on Nov. 24, 2009, in Minneapolis, Minn.

"Our group was working on very basic research on feedback flow control for years," says lead researcher Stefan Siegel, referring to efforts to use sensors and adjustable parts to control how fluids flow around airfoils like wings. "For an airplane, when you control that flow, you better control flight–for example, enabling you to land a plane on a shorter runway."

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