Within the project extensive results have been achieved, selected key results are:
- Novel structuring and replication technologies were developed to reproduce the micro pillar structures required for passive air lubrication. Improved production processes for embossing of microstructures on thermoplastic and silicone material.
- Experimental and numerical investigations revealed possibilities, challenges, and limitations of air retaining surface structures. A complex dependence of air layer durability, drag reduction, biofouling prevention, water depth, flow speed, material composition and industrial manufacturability exists. This indicates that compromises are necessary.
- Geometry and size of surface structure were determined by theoretical calculations and simulations on high performance computer cluster which showed frictional drag reduction of the order of 10% is possible. Depending on ship speed and length, the size of the surface structure has to be adapted.
- Experimental setups were retrofitted with devices for monitoring and controlling dissolved oxygen levels to realise steady conditions.
- Friction force experiments were performed under near-operational at showed a drag reduction of up to 9% at higher speeds. The degassed foil also showed a drag reduction at low speeds.
- Prevention of biofouling were demonstrated for an intact air layer.
- Technologies for air layer monitoring were developed, evaluated and tested.
- Industrial production and application procedures were developed.
- Two real world applications were performed, one on a research vessel and another on a container vessel validating application procedures and operability of the product.
- The environmental benefit to the global fleet was determined by updating the ship emission model STEAM including the effect of friction reduction from AIRCOAT
- A cost benefit analysis performed to determine the potential economic impact of the AIRCOAT technology showing that a monetary advantage will increase with increasing fuel costs.
- Noise emissions reduction was proven with noise dampening increasing with increasing air layer thickness.
- Six key exploitation results were defined leading to a commercialisation plan: AIRCOAT foil itself as a product, a prototype machine to continuously produce foil covered with a sub-micron surface structure, a wall function applicable for CFD calculations, the general model of AIRCOAT that demonstrated passive air lubrication, a semi-industrial production process and the updated STEAM model.
