A New Turbine-Sail Coupled Propulsive System for Autonomous Sailboats*

Autonomous sailboats are good candidates to perform long-term missions in oceans since they are wind-propelled. Furthermore, wind turbine is a useful device that can provide autonomous sailboats with necessary electrical energy to support controller, drive rudder and sail. Some current applications for onboard wind turbines can reduce fuel demand of autonomous power sailboats. Apart from necessary electrical energy supply, autonomous sailboats also need enough propelling forces to move efficiently in the direction of the course.In this paper, we propose a new turbine-sail coupled system that utilizes wind sources by adding two vertical wind turbines on both sides of the sail. Experiments are conducted in a wind tunnel. The results show that the system can increase the maximum propelling force when sailing downwind and allow further regulation of the force by slowing the rotation speed of wind turbine on one side.