SSS 2008-07-08

（单词翻译）

This is Scientific American's 60-Second Science, I am Cynthia Graber. This'll just take a minute.

 Whales and dolphins were molded by evolution to glide¹ through water. We’ve been trying to create streamlined designs ourselves for structures such as wind turbine blades. Now researchers are examining the flippers, fins³ and tails of our water-dwelling cousins to learn how to improve engineering designs. Doctor Frank Fish—yes, that’s really his name, from West Chester University in Pennsylvania presented this research July 8 at the Society for Experimental Biology’s annual meeting in Marseille.Here’s one example of the way Doctor Fish’s research is being applied⁴. Whale flippers have a bumpy⁵ edge. This makes little sense to engineers. They’ve designed structures like wings and blades that ensure a steady air flow. But it turns out the unsteady flow over this more complex shape increases lift and reduces drag much better than any previous manmade design. It has to do with something called vortices. These are small tornado-shaped water formations in an animal’s wake. The bumps on a whale’s flipper² help form vortices that generate more lift, more smoothly⁶. Engineers are using this insight to design an entirely⁷ new wind turbine blade so that we can generate power from wind as efficiently⁸ as whales and dolphins fly through the water.

Thanks for the minute for Scientific American's 60-Second Science, and I'm Cynthia Graber.