Takeoff simulation of eVTOL airplane with coaxial propellers by fluid–rigid body interaction

Abstract In this study, we adopt the coupled fluid–rigid body simulation using the moving computational domain method and the multi–axis sliding mesh method to the takeoff, hovering, and yawing flight of electric vertical takeoff and landing aircraft. The aircraft model has four pairs of coaxial propellers, and the computational domain is divided into three domains to move the aircraft and eight propeller domains to rotate the propellers. As a result, we clarify the behavior and aerodynamic force of the aircraft when the input values are determined by the automatic control. The results in the flow field also show that the downwash spreads in a crisscross pattern on the ground, that the wind reaches different ranges on the ground depending on the flight altitude, and that the coaxial propeller causes a asymmetry in the velocity field during yawing. Consequently, we conclude that this method is effective for the flight simulation of electric vertical takeoff and landing aircraft.