The humpback whale has pronounced bumps or tubercles along the leading edge of its pectoral flippers (above left). A idealized model of the flipper (above upper right), which was tested in a wind tunnel, demonstrated that the tubercles enhanced hydrodynamic performance…
airblade, turbine, windmill
…particularly by delaying stall (i.e., dramatic loss of lift) of the flipper with increasing angle of attack. The tubercles were placed on biomimetic windmill blades (above lower right) and tested by the Canadian company WhalePower. In August 2009, the tubercle technology design for windmills was honored as a finalist for the INDEX Award in Copenhagen, Denmark (below). Application of the tubercle technology has been taken up by the companies WhalePower for use in wind turbines, fans, pumps and compressors, Envira-North Systems for large ventilation fans, and Fluid Earth for surfboard skegs.
Frank Fish, biology professor at West Chester University in Pennsylvania, discovered that by adding rows of similar bumps to turbine blades he could reduce drag and noise, increase speed to changing wind direction and boost the power harnessed by 20 percent.
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