De-icing aircraft with chemicals is expensive, environmentally unfriendly and time-consuming. For the last decade researchers have been exploring the possibility of building planes with hydrophobic, or water-repellent, materials that would not require de-icing.
But now, researchers from MIT report that this approach is flawed. Although a surface might be water-repellent, it may not be ice- or frost-repellent. Their findings appear in the journal Applied Physics Letters .
“Water can go directly from a vapour stage to a solid state,” said Kripa Varanasi the study's lead author and a professor of mechanical engineering at MIT. “When ice forms this way typically called frost on a super hydrophobic surface it can pretty much coat up the entire surface.”
The result is a surface covered in frost that is no longer hydrophobic, but incredibly hydrophilic, or water-attracting, he said.
Varanasi believes that frost buildup can be better controlled by creating a surface with nanoscale texturing.