Aerodynamic and Structural Design of the Composite Propeller for Near Space Vehicles

In order to make full use of the power of engine and reduce the energy consumption, propeller need to be highly efficient and lightweight to satisfy the High Altitude Airship's (HAA) requirements during the high altitude and long endurance flight period. This paper presents an efficient aerodynamic and structural design procedure of the propeller for HAA. First, according to the operating conditions of a HAA's propulsion system, the chord and twist distribution of the propeller blade are optimized to provide the maximum efficiency by GA optimization and propeller vortex theory. Next, the finite element parametric model for the blade is established. Then, based on the aerodynamic characteristics of each blade element, the pressure distribution of blade is calculated by XFOIL, and loaded into the finite element model to investigate the strength of the composite blade. After that, the detailed ply layup and the weight of the blade are obtained by the structural optimal design. The aerodynamic and structural design results show that, compared to the initial blade, the efficiency of the optimized blades which exhibit more mass saving is increased.