The average humpback whale weighs about 36 tons, yet it is one of the most graceful swimmers, divers, and jumpers in the sea. WhalePower's new wind turbine technology owes its performance to
what it has learned from from studying just what makes the humpback
whale so aerodynamic.
Frank Fish (yes, it's his real name), whose field just happens to be biomechanics, actually came about his observations of the humpback whale serendipitously when he saw a sculpture of a humpback with what he thought were misplaced tubercles on the whale's flipper. The artist had placed them on the "leading" edge of the flipper, not on the underside of the flipper, where Fish "knew" they should be because of his study of fluid dynamics (i.e, smooth edges are most aerodynamic).
The artist was correct, however, and Fish's further research indicated that at least part of the science of fluid dynamics was wrong. The tubercle placement on the humpback whale's flippers and tail is a major part of the reason the great mammal is so aerodynamic - or as MIT's Technology Review called it, hydrodynamic. (reference)
Early wind tunnel tests of model flippers with tubercles by the U.S. Naval Academy showed that wind drag was reversed by 32 percent and lift was increased by eight percent. Other studies showed similar results. Corresponding design changes to airplane wings would seem to make sense considering these results....
But Fish capitalized on this knowledge by inventing a "Tubercle Technology," through his company, WhalePower. The technology, licensed by Envira-North Systems Ltd, first became available in energy saving fans, ventilators (Hurricane turbines), and even curtains.
Now WhalePower is applying its TubercleTechnology to create wind turbines.
Take a look at the design of the blade.
This tubercle design operationally keeps air attached to the blades, thereby managing the flow of air and increasing the lift of the blade -- two areas of concern in the development of wind turbines. To date, in fact, no wind turbine performs better in low wind conditions; low wind can literally shut down a smooth-edged turbine. Additionally, Tubercle Technology offers quieter operation, greater stability, and with little to no tip stalling.
WhalePower's Tubercle Technology is one of the finalists of the INDEX Awards 2009. Winners of the awards will be announced later this summer.
INDEX, WhalePower, Envira-North, Wikapedia via Popular Mechanics