空力性能と空力騒音を考慮した空飛ぶクルマのロータについて

抄録

For Electric Vertical Take-Off and Landing (eVTOL) aircraft, aerodynamic efficiency and noise are two of the most important performance indices. A single coaxial rotor and quad coaxial rotors are studied from these two viewpoints. A coaxial rotor has larger efficiency such as Figure of Merit at hover and equivalent lift-to-drag ratio in forward flight than a single rotor. However, the noise generated from the coaxial rotor is higher than that from the single rotor mainly due to the interaction between the upper and lower rotors. Quad coaxial rotors have smaller efficiency than an isolated coaxial rotor because of the interaction between the rotors. However, the noise generated from the quad coaxial rotors is lower than the simple sum-up of four single units of coaxial rotors with no interference between them.