Aerodynamics of wind-assisted ships: Interaction effects on the aerodynamic performance of multiple wind-propulsion systems

The shipping industry is currently under pressure to reduce its pollutant emissions and, thus, to alleviate its negative impact on the environment and human health. With this aim, in the last years, the International Maritime Organization issued significant measures to improve the energy efficiency of ships (see the Energy Efficiency Design Index) as well as restrictive regulations to limit the amount of contaminating emissions from seaborne transport. Arguably one of the most impactful measures will be enforced at the commence of 2020 when the world fleet will have to use cleaner fuels or otherwise will need to install expensive exhaust gas cleaning systems (known as scrubbers) to comply with the new regulations. The use of cleaner and more expensive fuels will increase the ship operating costs and this, in turn, will make investments into fuel-saving devices more attractive....