Study on the Aerodynamics Interaction Between Propeller and Stratospheric Airship with Multi-propeller Layout

The aerodynamics interaction between propeller and Euler-shaped stratospheric airship with muti-propeller layout is studied through computational fluid dynamics method. It is found that due to the airship body, the thrust of the front propeller increases and the torque decreases. The thrust and torque of the rear propeller are obviously increased. As for the side propeller, its thrust is greatly influenced by the airship, while the torque is almost unchanged comparing with that of single propeller. Therefore, the efficiency of the front propeller is the highest which is about 7% higher than that of the single propeller, and the efficiency of the side propeller is the lowest. Compared with the resistance of the airship body alone, the pressure drag and viscous resistance of the airship with propeller interference are larger. Under the effects of the interference of propeller, the pressure drag of airship is increased by about 60%, which leads to the increase of total resistance of airship. On the windward side of the airship, due to the influence of the front propeller, the pressure surged in a small range. However, the rear of the airship was affected by the rear propeller, and the pressure dropped obviously. At the front of the side propeller, there is a local pressure drop on the airship surface.