Shark

SPEED THAT IS SKIN-DEEP

Is there anything more impressive than a shark chasing its prey? These giant fish move at lightning speeds, cutting through the water without the least resistance. The secret of their performance is the surface of their skin.

When fish swim, the water in contact with their skin becomes turbulent, creating resistance, an opposing force that impedes their movement. Although it seems smooth enough, a shark’s skin is finely textured, composed of tiny scales, calleddenticles, which are micro-ribbed lengthwise. When the shark swims, the water slides between the denticles, reducing the turbulence, or resistance, at the skin’s surface (riblet effect) and allowing this giant to move very quickly.

Researchers have studied the riblet effect extensively and found a range of applications for it, including competition swimsuits that take several hundredths of a second off a swimmer’s time.

The riblet effect is also used in boating and aeronautics. By fitting boat hulls with films whose texture resembles that of sharkskin, fuel consumption is reduced. Coating airplane walls with a micro-ribbed varnish gives the same result…in the air rather than the water, of course.

For more information on the animal:
Shark

For more information on the technology:
Shark skin study