Due to no design guidelines available for the hubless propeller, based on the relative inflow velocities together with blade root strength considerations, the Ka -series propeller's blade geometry was re-designed with an inversion of the thickness distribution of the sections. Accordingly, the blade geometry model for hubless rim-driven propulsors was designed, then three types of hubless rim-driven propulsors' models were established and calculated numerically. The results show that thrust coefficients and torque coefficients for hubless rim-driven propulsors are similar to the ducted Propeller's. Due to no hub, with the new thruster the hub-vortex is avoided and the cavitation is minimized.
