Floating like a butterfly

Not so long ago researchers at Tufts University in Maryland announced that they were studying the light scattering and heat dissipating properties of butterfly wings to find ways of improving microchip design. These studies have provided a useful understanding of the optical and thermal properties of microchips, which, like butterfly wings, consist of finely structured thin films.

Now, it looks like the Lepidoptera family is set to influence mankind again, with researchers at Israeli materials specialist Polymate claiming to have made a breakthrough in the design of helicopter rotor blades. Polymate’s blade coating design – which both increases the effect of airflow on the blades and reduces vibration and aerodynamic resistance – follows intensive studies carried out into insect flight dynamics, or, more specifically, the scale-coated wings of the cabbage butterfly.

It was noticed that the coating on the butterfly wings both increases the wing lift and decreases vibration and noise from the flying butterfly.

Polymate developed a metallic version of the butterfly wing coating and applied it to a propellor blade model which was then tested alongside a non-coated model in a wind tunnel. The performance of the two models was markedly different. The new coating was found to increase pressure loading by 65%, reduce flap resistance, and reduce frequency waves by 15%.

Polymate claims that helicoptors using this coating will beneft from vastly improved flight perfomance and a reduction in fuel consumption. Furthermore, the company estimates that before the first change of a turbine, an average helicoptor like an Mi 8 will use upto 130ton less fuel.