The European Commission is funding Aircoat with a total of 5.3 million euros, of which KIT is receiving around one million euros. The scientific coordination is the responsibility of physicist and nanotechnology expert Professor Thomas Schimmel at KIT. The project started on May 1, 2018 and will run for three years. The Fraunhofer Center for Maritime Logistics and Services CML in Hamburg is acting as project coordinator.

Aircoat (Air Induced friction Reducing ship Coating) aims to develop a passive air lubrication technology for ships that contributes to the protection of the oceans and the atmosphere. A self-adhesive film applied to the ship's hull creates a thin layer of air that significantly reduces frictional resistance and at the same time acts as a physical barrier between the hull surface and the water. This significantly reduces the ship's fuel consumption and exhaust emissions. The air layer also reduces the radiation of ship noise. In addition, it prevents marine organisms from settling on the hull, known as fouling, as well as the release of biocidal substances from underlying coatings into the water.

Technology copied from nature

The innovative air coating is a bionic application - the technology is copied from nature. Aircoat is based on the Salvinia effect, which was jointly discovered by botanist Professor Wilhelm Barthlott from the University of Bonn and physicist Professor Thomas Schimmel from KIT. This effect enables certain plants such as floating ferns (Salvinia) to breathe under water. To do this, they keep a thin layer of air on the surface of their leaves, which has hair-like structures and is extremely water-repellent. The Aircoat project is now technologically implementing this effect, which enables layers of air to be held on surfaces under water, on a self-adhesive film system.

The scientific coordinator of Aircoat, Professor Schimmel, who works at the Institute of Applied Physics (APH), the Institute of Nanotechnology (INT) and the Center for Functional Nanostructures (CFN) at KIT, researched the salvinia effect with his working group in the Ares project funded by the German Federal Ministry of Education and Research, in which KIT and the universities of Bonn and Rostock were involved, as well as in a project funded by the Baden-Württemberg Foundation. "Once we understood the salvinia effect, we recognized the enormous economic and ecological potential of a technical implementation," reports Schimmel. "We developed a method for producing an artificial surface that mimics the effect in the laboratory. An early prototype that we put under water more than five years ago is still covered with a permanent layer of air!"

The Aircoat consortium is optimizing the new technology and investigating the surface properties experimentally and numerically. The researchers will then demonstrate the efficiency and industrial feasibility in the laboratory, on research vessels and on container ships. A comprehensive validation process will prove the benefits for the economy and the environment. In Aircoat, scientists from various disciplines - from applied physics, nanotechnology, experimental and numerical fluid mechanics and bionics to marine engineering and ship emission modeling - work together with industry experts from the fields of ship coating, ecotoxicology and self-adhesive film technology as well as container ship operators. as