Aerodynamic Analysis of a Hexacopter with an Inner Tilted-Rotor Configuration During Hovering

The present work is aimed at investigating the arrangement design of an inner tilted-rotor hexacopter to optimize aerodynamic performance with different rotor spacing ratios (s/D) and dihedral angles (β). Both experiments and numerical simulations were applied for different rotor arrangements, and the better rotor agreement was related to both higher thrust and lower power consumption. The results show that hovering efficiency is mainly affected by rotor spacing ratios and dihedral angles. Appropriate rotor spacing with moderate rotor interference from the blade tip vortices, as well as downwash flow, reduce vortex distortion and fragmentation. The results show that a hexacopter with inner tilted-rotors obtains a larger thrust and smaller power with a high factor of merit (FM) at s/D = 1.6 and β = 40°, and this is considered to be the optimal arrangement for a hexacopter with excellent aerodynamic characteristics.