Experimental Evaluation and Flight Simulation of Coaxial-Rotor Vehicles in Icing Clouds

摘要

This paper has described an experimentally derived model for the effect of ice accretion on power and thrust on an electrically driven coaxial-rotor system typical of unmanned aircraft. This model was integrated into a flight simulation model of a cargo UAV operating in icing conditions to assess the effect of icing on flight performance and controllability. The coaxial-rotor system was constructed from commercially available motors and rotors (0.46-m-diameter rotor). Force and torque sensors on each motor enabled independent measurement of the torque and thrust of the upper and lower rotors. The MVD of the icing cloud was controlled, and LWC of the icing cloud was quantified. Icing tests were conducted at temperatures of -5, -10, and -15 ℃ and at constant rotor shaft speeds of 3500,4000, and 4500 rpm. Experimental results showed a significant difference in ice accretion rates between the upper and lower rotors in the coaxial pair, with the lower rotor showing significantly lower effect of icing than the upper rotor. In the commercially available rotors tested, ice shedding occurred frequently.