Researchers Examine Owl Wings to Cut Wind Turbine NoiseEngineering360 News Desk | August 17, 2015
Researchers say that owls are equipped with “stealth technology” that allows them to swoop on their prey in near-silence. The birds’ feathers are capable of absorbing sound and suppressing vibrations, meaning they can fly undetected.
The team—from Dalian University of Technology in China—used lasers and cameras to compare the feathers of the long-eared owl, eagle and pigeon during flight. They found an owl’s feathers turn energy into heat as it flies, in turn silencing its wings.
Research showed that the long-eared owl has a superior “damping” skill, meaning it can remain stable and eliminate mechanical noise. It not only manages to suppress aerodynamic noise when gliding, but also mechanical noise caused by vibration during flying, the researchers say.
Much of the noise caused by a wing—whether it is attached to a bird, a plane or a fan—originates at the trailing edge where the air passing over the wing surface is turbulent. The structure of an owl’s wing serves to reduce noise by smoothing the passage of air as it passes over the wing—scattering the sound so their prey can not hear them coming. The findings may help reduce the noise of wind turbines.