Paint it FAST! Posted on 12 Jan 12:23
An innovative paint system may make everything faster and more efficient. The inspiration and model for the comes from nature. The scales of fast-swimming sharks have evolved in a manner that significantly reduces drag.
The challenge was to apply this information to create a paint that could withstand the demands of aircraft. With temperature environments of -55 to +70 degrees Celsius, intense UV radiation and high speeds. Yvonne Wilke, Dr. Volkmar Stenzel and Manfred Peschka of the Fraunhofer Institute for Manufacturing Engineering and Applied Materials Research IFAM in Bremen, Germany, developed not only a paint that reduces but also the associated manufacturing technology. In recognition of their achievement, the team was awarded the 2010 Joseph von Fraunhofer Prize for their pioneering efforts.
The paint is a sophisticated formulation. An important part of the recipe are the, which ensure that the paint is durable and withstands UV radiation, temperature change and mechanical loads. "Paint offers more advantages," explains Dr. Volkmar Stenzel. "It is applied as the outermost coating on the plane, so that no other layer of material is required. It adds no additional weight, and even when the airplane is stripped - about every five years, the paint has to be completely removed and reapplied - no additional costs are incurred. In addition, it can be applied to complex three-dimensional surfaces without a problem."
The next step was to clarify how the paint could be made on a mass-production scale. "Our solution consisted of not applying the paint directly, but instead through a stencil," says Manfred Peschka. This gives the paint its sharkskin structure. The unique challenge was to apply the fluid paint evenly in a thin layer on the stencil, and at the same time ensure that it can again be detached from the base even after, which is required for hardening.
When applied to every airplane every year throughout the world, the paint could save a volume of 4.48 million tons of fuel. This also applies to ships: The team was able to reduce wall friction by more than five percent in a test ship construction testing facility. Extrapolated over one year, that means a potential savings of 2,000 tons of fuel for a large container ship. With this application, the algae or mussels/barnacles that attach to the hull of a ship only complicate things further. Researchers are working on two solutions for the problem. Yvonne Wilke explains: "One possibility exists in structuring the paint in such a way that these clinging organisms cannot get a firm grasp and are simply washed away at high speeds. The second option aims at integrating an anti-fouling element, which is incompatible for the creatures."
Irrespective of the fuel savings, there are even more interesting applications with wind energy farms. Air resistance has a negative effect on the rotor blades. The new paint could improve the efficiency of the systems as well.