Wake Effects of Free-Wake Model on Aeroelastic Behavior of Hovering Rotors

The wake effects on aeroelastic deflections and aerodynamics for the isotropic and composite rotor blades have been investigated. To take into account the large deflections and rotations of rotor blades, a large-deflection beam modelwas used. A free-wake model basedon vortex-lattice method wasused to obtain the aerodynamic forces while considering wake effects. Newton–Raphson iteration method was applied to the aeroelastic analysis to obtain the numericalsolutions.The flap,lag,andtorsiondeflectionsconsideringwakeeffectsbyusingthefree-wakemodelwere investigated and compared with the results using two-dimensional quasi-steady model. Finally, aerodynamic changes after aeroelastic deflections were investigated.

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