Theoretical and Experimental Study of Axial Autorotation of Simple Rotary Decelerators

Autorotation in a steady-state axial motion is investigated theoretically and experimentally. A simplified model presents the major physical parameters affecting this phenomenon, giving an insight into the phenomenon and the influence of various parameters. A more detailed model, based on a multibody dynamic approach, is also used to describe the phenomenon more accurately. A series of experiments of a rotor model in a wind tunnel is carried out using two kinds of rotor blades operating at a wide range of freestream velocities and pitch angles. The experimental results are used to verify the theoretical results obtained by the simplified and the detailed models. Good agreement between the calculated and measured results is shown.