Cycloidal Rotor Aerodynamic and Aeroelastic Analysis

Cycloidal rotors consist of an arrangement of blades that rotate and pitch about a central drum. The blades are aligned with the drum axis. By pitching harmonically with respect to the azimuth, they create a net propulsive force which can propel an aircraft. The aerodynamic response of a cycloidal rotor in various environments has been studied using a simplified analytical model resolved algebraically and by a multibody model resolved numerically. An computational fluid dynamics model has also been developed and is used to understand the cycloidal rotor behavior in unsteady flow. The latter model is also used to investigate the influence of the rods used to hold the blades on the aerodynamics of the rotor. The models are also used to calculate the efficiency and the stability of the cycloidal rotor in various configurations. The three developed models are validated using a set of data obtained from experiments conducted by three different parties. In all the experiments, the spans and radii were in the order of a meter. The use of cycloidal rotors as a replacement for the tail rotor of a helicopter has also been studied. Preliminary analysis suggests that they can potentially cut down the propulsive energy demand of a helicopter by 50% at high velocities. An aeroelastic model is used to assess the influence of flexibility on the system. Different cycloidal rotor configurations have been considered.