Wake Effects on Aeroelastic Stability of Hingeless and Bearingless Rotors

摘要

In the present work, a study of the wake effects on the aeroelastic stability of hingeless and bearingless helicopter rotors was investigated in forward flight. A nonlinear beam model based on the large deflections theory was employed to evaluate the aeroelastic responses. To calculate the airloads of the rotor blades, three different aerodynamic approaches were used: a 2-D quasi steady with a Drees linear inflow model, the BET with a Drees linear inflow model, and the BET with a free-wake method. As a result of the differences in the aerodynamic methods, the results of the periodic tip deflection exhibited discrepancies. In addition, the flap, lag, and torsion damping values obtained from the stability analyses of the hingeless rotor blades were compared with those from previous studies.