Experimental and Computational Investigation of Aerodynamic Interactions in Quadrotor Configurations

Overview & Synopsis

The influence of interactional effects on quadrotor performance in forward flight was evaluated taking into account square and diamond configurations, forward and backward tilt angles, and a range of hub spacings including overlapping blades. The analysis was based on the wind-tunnel measurements and simulations from four midfidelity computational methods and the high-fidelity tool. The outcome indicates that the efficiency of a diamond configuration improves by 5% in comparison with isolated rotors for nonoverlapping rotor spacings, while the interactions in square alignments are detrimental for all analyzed test cases with the optimum at 0.04D blade overlap. The trend is more pronounced for the backward rotor tilt with intensified interactions, for which the efficiency of the diamond configuration increases by 11% at 1.2D rotor spacing. The computational results showed good agreement with the measurement data for the forward rotor plane tilt; however, for the backward tilt angle, the spread between the calculated values, especially for torque, could be observed with the general trends maintained. The study shows negligible impact of the rotor phasing on the quadrotor efficiency.