Anti-icing surface could revolutionize deicing

Researchers in the United States have developed the first passive anti-freeze surface that could revolutionize the management of ice accumulation in airplanes, cars and even roads.

A study released by Virginia Tech this week at Applied materials and ACS interfaces, asserts a proof of concept to keep surfaces 90% dry and frost free indefinitely, without the use of chemicals or energy.

"For this project, we do not use any type of special coating, chemicals or energy to overcome the frost," the study's lead author, Farzad Ahmadi, told the press. "Instead, we use the unique chemistry of the ice itself to prevent frost formation."

Traditional de-icing approaches rely on the use of antifreeze chemicals – including salt spray on roads – or heat.

There are also special coatings that prevent the formation of frost, but these coatings tend to be easy to use.

The approach of Virginia Tech uses a structural shaping in the form of a microscopic network of raised grooves, modeled on untreated aluminum. The ice is then formed into bands in "sacrificial" low pressure zones.

These low pressure zones draw moisture from the air on the nearest ice band, keeping the overlapping intermediate zones free of frost, even under moist sub-freezing conditions.

"The real power of this concept is that the ice bands themselves are chemistry, which means that the material we use is unimportant," said Jonathan Boreyko, an assistant professor in the Department of Biomedical Engineering and Mechanical Engineering. Virginia Tech.

"As long as you have this sacrificial ice model, the material you use can be just about anything. There are so many possibilities.

While engineers say that aircraft wings will probably be the first application, the windshields of cars are also an option for anti-icing technology.

Boreyko said that the technique is a new application of a well-known principle.

"We have known the trick for centuries," he said. "You drop a low pressure chemical, like salt, and you keep everything around it dry enough.

"But now we are doing this eternal effect, and we are rendering its distribution rational."