A team of biologists and engineers from Harvard University and the University of South Carolina recently joined forces to investigate how sharkskin could help improve the aerodynamic performance of planes, wind turbines, drones, and cars. Their findings were recently shared in the Journal of the Royal Society Interface.
The research looked at how the skin of sharks, which is covered by thousands of small scales, or denticles, impacts drag, or could be used to increase lift. The team began by working with the skin of a shortfin Mako, which is the fastest shark in the world. Their denticles have three raised ridges, like a trident.
The team utilized micro-CT scanning to image and model the denticles in three dimensions. Then they 3-D printed the shapes on the surface of a wing with a curved aerodynamic cross-section, or airfoil, to measure their effect on lift and drag. The researchers tested 20 unique denticle size configurations, as well as rows and row positions, on airfoils that were placed inside a water tank. They found that in addition to reducing drag, these denticle-shaped objects increased lift. They basically acted like high-powered, low-profile vortex generators.
The shark-inspired vortex generators achieved a lift-to-drag ratio improvement of up to 323 percent compared to an airfoil without one. Vortex generators are the small, passive devices on cars and planes designed to alter the flow of air over the surface of a moving object in order to make it more aerodynamic. Most have a blade-like design. The team plans on using this preliminary data to develop more real-world applications for the technology.