Penguins are flightless birds, and yet, these animals hold the clue in helping humans fly planes more safely, a new study revealed.
The ability of penguins to live and survive in environments where the temperature could drop to -135 degrees Fahrenheit might be the key in preventing airplanes from crashing, according to researchers from the University of California, Los Angeles (UCLA).
UCLA researcher and Engineering Professor Pirouz Kavehpour said his interest in penguins was piqued while watching a nature documentary. Antarctic penguins or Gentoo penguins could habitually hop in and out of extremely cold water without freezing. These animals manage to keep ice from coating their wings and feathers, and this made Kavehpour curious.
From then on, Kavehpour, along with Judy St. Leger and other experts, conducted a thorough study on Antarctic penguins. The team utilized a scanning electron microscopy to examine penguin feathers which were donated by SeaWorld San Diego.
Researchers found that these penguin feathers contained tiny pores that trap air and make the surface of the feather repel water incredibly. The penguins apply oil, which is produced by a gland near the base of their tail, to their feathers. These remarkable attributes make penguins superhydrophobic.
On surfaces that are superhydrophobic, water droplets bead up and sit on the surface like spheres, experts said. The principle can also be found in the leaves of the lotus plant.
Kavehpour and his colleagues said that the sphere-like geometry enable ice formation to be delayed, especially because heat cannot flow out of the water droplet if the droplet itself does not make contact with the surface.
"Heat flow could be compared to traffic. If you have a freeway that turns into a tiny, two-lane road, the traffic will back up," explained Kavehpour. He said that heat does not flow well from the large cross-section of the middle of the water droplet to the small cross-section where the droplet supposedly makes contact with the feather surface.
The team compared the feathers of Gentoo penguins to the feathers of penguins that live in much warmer climates. They found that the latter do not have the small pores that Antarctic penguins have, and these warmer climate penguins use a different kind of oil which does not repel water.
Researchers believe that Antarctic penguins' anti-icing tricks could be applied in designing airplanes. If there is ice on the wings of an airplane, rudder and flaps can change the aerodynamic properties of the plane and eventually cause it to crash. Lots of time and money is spent to put chemical de-icers to planes which fly during winter, but if scientists find a way to make the surface of planes superhydrophobic, the cost may be reduced, and the planes could become longer-lasting and more environmentally friendly, researchers said.
The study, entitled "Ice Formation Delay on Penguin Feathers," was presented at the 68th annual meeting of the American Physical Society's Division of Fluid Dynamics in Boston, Massachusetts.
Photo : David Stanley | Flickr
