[ad_1]
A UK study revealed how microstructured fins on owl feathers enable silent flight, a discovery that could pave the way for noise reduction for future aircraft.
The study was conducted by researchers from City, University of London, led by Professor Christoph Bruecker, and was published in the Institute of Physics journal, Bioinspiration and biomimicry.
Their research outlines their translation of the detailed 3D geometry data of typical owl feather examples provided by Professor Hermann Wagner of the RWTH University of Aachen in Germany into a biomimetic airfoil to study the aerodynamic effect on special filaments at the leading edge. some feathers.
The results of the study showed that these structures function as arrays of fins that consistently rotate the direction of flow close to the airfoil wall and maintain the flow longer and with greater stability, avoiding turbulence.
The city’s research team was inspired by the complex 3D geometry of the extensions along the front of the owl’s feathers. These were reconstructed by Professor Wagner and his team in previous studies using high-resolution micro-CT scans.
Close-up image of the notched feather from an owl.
Image credit: Professor Christoph Bruecker
After being transferred into a digital shape model, flow simulations around those structures (using computational fluid dynamics) clearly indicated the aerodynamic function of these extensions as finlets, which rotate the direction of flow consistently, said the team. This effect is known to stabilize the flow over an airfoil, typical of owls as they flap their wings and glide.
Using flow studies in a water tunnel, Professor Bruecker also demonstrated the reverse flow hypothesis in experiments with an enlarged finlet model.
His team found that instead of producing swirls, the fins act as thin guide fins due to their special 3D curvature. The regular arrangement of these fins on the wingspan, therefore, transforms the flow direction near the wall in a uniform and consistent way.
Wingspan of an owl.
Image credit: Professor Hermann Wagner
The team plans to use a technical implementation of such a swept wing airfoil in an anechoic wind tunnel for further acoustic testing. The researcher believes that the result of this research will prove important for future laminar wing design and has the potential to reduce aircraft noise.
Sign up for the E&T News email to get amazing stories like this delivered to your inbox every day.
[ad_2]Source link
