有翼タンデムロータのロータ間距離とロータ主翼間距離に対するホバリング時の空力特性

抄録

The aerodynamic characteristics of the rotors and wing with the distance between rotors d/2R and the distance between rotors and wing z/R of a winged tandem rotor with the cyclic pitch control of the rotor and the pitching, rolling, and torque balance of the rotors were investigated using rFlow3D which is a CFD code on hover. Results showed that the lateral cyclic pitch eliminated the head-up moment of the front rotor caused by the overlap, but increased the rotor efficiency loss and the induced power overlap factor for d/2R ≧ 0.5. Compared to tandem rotors, winged tandem rotors of z/R = 0.2 increased the rotor-induced power by up to 27% because the rotor thrust increased to balance the wing download. The wing download was about 18% of the rotor thrust for d/2R ≦ 0.5. The local wing download increased due to the downwash caused by the interference of the blade tip vortices of the front and rear rotors. As the z/R of the winged tandem rotor increased, the rotor-induced power increased, and the wing download to rotor thrust ratio decreased.