Wind propulsion systems cannot be considered as simple thrust generators: they affect the vessel sailing operations by introducing steady drift and rudder angles, necessary to ensure that the ship can sail along a straight course. This causes an increase in vessel hydrodynamic resistance that needs to be deducted from the WASP aerodynamic thrust. The result is the net wind assistance contribution.
The magnitude of the WASP-induced hydrodynamic resistance depends on the ship design, the size of the wind assist installation and the wind conditions. Subject to the combination of these factors, the hydro losses can amount to a significant portion of the aerodynamic thrust. The good news is that there are several precautions that can be taken to mitigate such losses. For example, appendages like bilge keels, when appropriately designed, can help maximize the performance of your WASP vessel.
Download our scientific paper “Low aspect ratio appendages for wind-assisted ships” and get in contact to find out more.