Would you ever think that the owls’ wings could reveal the secret to solve the wind turbines noise problem? Hidden wonders of nature are all around us, largely invisible to our eyes, and some of them may have important implications for the renewable energy industry as well.
One of the limits of wind power plants is noise, which prevents them to spread across populated areas. Wind turbines generate zero-emission electricity, but the rotor used to convert the blades kinetic energy into electricity produces too much noise, with negative effects on earth and marine life.
Researchers from China and Japan are taking inspiration from the owls’ wings to improve the noise of wind power plants.
Indeed, owls are predators that exploit their silence to surprise their prey. Owls’ wings have a relatively a small opening, but wide if compared to the total weight. It means that compared to other birds the owls need a lesser effort to stay in the air.
Professor Hao Liu, from Chiba University, Japan, said: “Owls are known for silent flight, owing to their unique wing features, which are normally characterised by leading-edge serrations, trailing-edge fringes and velvet-like surfaces. We wanted to understand how these features affect aerodynamic force production and noise reduction, and whether they could be applied elsewhere.”
The research required the use of advanced computer modeling. It analyzed mathematical models of owl wings with and without leading-edge serrations using large eddy simulations used in computational fluid dynamics to simulate air flows. They also used particle image velocimetry and force measurements in a low-speed wind tunnel.