Abstract
The movement of the wing of the cycloidal propeller can be described as combination of in-phase pitching and heaving oscillation. Under consideration of this, characteristics of the propeller are analyzed with unsteady airfoil theory by Karman and Sears. Reduced frequency of the wing in this case is decided by the ratio of half chord length to rotational radius and is unrelated to rotational speed. It can be clarified that reduced thrust depends on the amplitude of the oscillation and the moving velocity of the propeller. Results of quasi-steady and unsteady analyses are shown in the vector diagrams, and unsteady flow effect by wake vortices generation is inferred by comparing both results. Calculated results of the power for generating thrust and the thrust efficiency are also discussed.
