Biofouling, an industry name for accumulation of microorganisms, plants, and/or animals on wetted structures, adds to fuel costs for the military and shipping industry as well as increasing drag up to 15 percent. According to Live Science, the Navy spends about $50 million just on bio-fouling and paints laced with deadly biocides curb problem, but these substances are toxic to marine life. Although sharks are also attacked by biofouling, they stay clean. How is this possible?
A shark's scales are made of a hard material called dentin and act as tiny teeth. These special scales are also pointed backward, so they feel smooth when stroked from head to tail but rough in the other direction. The scales also act as armor for a shark, creating tiny vortices that reduce drag, and allow sharks to swim silently.
A synthetic shark skin of elastic silicone that makes it harder for barnacles to gain a foothold has been created in Bremen, Germany by Ralph Liedert of the University of Applied Sciences. "While simpler in design than shark scales, the ship skin reduced biofouling by 67 percent in tests," states Live Science. "With the fake skin applied, a ship moving at 4 to 5 knots becomes self-cleaning, removing most organisms."
The University of Florida, in separate work funded partially by the U.S. Navy, has developed a similar coating, made of tiny diamond-shaped scales that flex in and out to impede the growth of organisms. The spore settlement has been reduced by 85 percent. While the high-tech skins could reduce costs for the shipping industry, they could prove a strategic advantage for the military.
