Propeller/stator propulsors for autonomous underwater vehicles

The use of appropriate propulsion devices for autonomous underwater vehicles (AUVs) is important from the point of view of higher propulsive efficiency and directional stability. In this paper, a design methodology for a propeller/stator combination behind an autonomous unmanned underwater vehicle is described. The design procedure is presented based on the three dimensional flow around the vehicle and the lifting line theory of propeller action with the associated formulation. The effect of variation of the axial distance between the propeller and stator and the number of the stater blades on the propulsor characteristics are systematically investigated. From the application of this method to a typical AUV the improvements in torque balance and propulsive efficiency are demonstrated.