Experiment and Analysis of Aerodynamic Performance of Coaxial Rigid Rotor
The high speed coaxial helicopters with rigid blades will be the future development direction of rotor aircraft,to gain insights into the effect of of the advance ratio and lift offset on the aerodynamic characteristics of coaxial rigid rotor,a trim strategy was developed and the wind tunnel test was carried out in the FL-52 wind tunnel of AVIC Aerodynamics Research Institute to investigate the performance of co-axial rigid rotor.The rotor aerodynamic performance in hover and forward flight conditions and the influence of lift offset were studied.The results indicate that the trim strategy is reasonable,and the trim results are satisfactory.The trim errors of hub torque,total torque of rotors and lift offset are better than±2 N·m,±0.5 N·m and±0.01 respectively.The efficiency of the upper rotor is greater than that of the lower rotor under torque balanced and unbalanced in hover.The efficiency of differential collective increases with the increase of coupled col-lective.In forward flight.The lift offset in forward flight can effectively improve the rotor aerodynamic efficiency at high forward ratio,but it is not significant at low forward ratio,increasing the lift offset will significantly increase the hub rolling moment of the upper and lower rotors.
万方数据
维普
