Aircraft de-icing is an important, but troublesome process. Spraying with antifreeze is expensive, inefficient, not ecological and time consuming. Not only the passengers’ itineraries are at risk, but it has a big financial impact on the airlines. Lost connections and plenty of unnecessarily burned fuel whilst waiting make winter an unwanted season by people in the field.
De-icing is an expensive process that costs about €1,500 per run. The US EPA estimates that de-icing chemicals costs airlines approximately $200M/year in the US alone.
Most current strategy to combat the problem employs nichrome (an alloy of nickel and chromium) for resistive heating of wings on B787. However, our solution based on nanocarbon heating technology has a spectrum of advantages over nichrome. We devised a few methods that make it fully scalable and thus heaters developed in this project can readily be deposited on a new wing or retro fitted on existing wing part.
Our current focus is on commercialization of these resistive heaters based on carbon nanotube technology. We have been evaluating properties of the material in terms of suitability to work in abrasive conditions over a wide temperature range, to which they would be exposed in aircraft de-icing environment.
Our development was based on a proprietary technology of manufacture of nanocarbon based heated paints. In brief, carbon nanotubes, graphene or other nanostructured type of carbon is dispersed in a suitable solvent. Such paint can then be deposited by a wide variety of methods (spray-coating, spin-coating, dip-coating, painting, printing, etc.) onto the wing part, which is mostly affected by ice accretion. Our specially developed paint assures extremely quick application time. Once electrical connections are made to the deposited heating layer, the system is ready to remove ice from the wings by electrothermal heating. The extremely flexible heating layer can be of any size and shape (covering also the most complicated structures). The thickness of the heated coating is in the range of 1-100 micrometers, which is extremely effective and lightweight.
During the course of this project, we also developed technology, which allows to deploy the heater without the need of direct paint deposition on the affected wing part. In such case, our technology allows for the formation of free-standing heating layers, which can be shipped in solid form and applied as patches onto critical areas for de-icing and anti-icing environment.
The heating layer patches can also be made of any size and thickness. The heating layer can easily reach 100°C, which has been found more than enough to remove unwanted ice. We are also capable of tailoring these heaters to reach temperatures of 400°C and above for applications requiring more severe conditions.
The heaters show extreme stability in terms of mechanical, thermal and chemical properties. Firstly, they are very flexible. We have found that millions of bending cycles of very high bending angles do not result in deterioration of the heating performance. The heaters themselves can be regarded as mechanical reinforcement due to excellent mechanical properties of nanocarbon materials. Furthermore, the heating performance and heater stability is unaffected by subjecting them to wide temperature range from extreme conditions such as –196°C up to 400°C. Lastly, the nanocarbon heating layers show unique resistance to corrosion and can be exposed to a spectrum of chemical environments without any deleterious effect to their performance. We have proven that they can operate with ease in highly acidic, alkaline and salty conditions. The heaters have also been proven to work with the same high performance in the presence of a variety of aircraft fluids such as hydraulic fluid, aviation fuel and others.
Dissemination activities for the project:
The project successfully created a new start-up company, by the name of CnergyTEC (www.cnergytec.com)
The video of the project can be found here:
https://youtu.be/9XyjFKEIdvE(opens in new window)Project Website (Thawing):
http://www.thawing.eu/(opens in new window)
