Multi-objective optimal design of the propeller for high altitude airships based on high efficiency and light weight

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 a multi-objective optimization design method of the propeller for HAA. The vortex theory is used to predict the propeller's aerodynamic performance and the non-dominated sorting genetic algorithm II (NSGA-II) is applied to solve the optimization problem. Then the optimization model which has two objectives of high efficiency and light weight of the propeller is established according to the conditions of the HAA's propulsion system. In addition, the effects of the various parameters including pitch angle, chord width, rotational speed and diameter on high altitude propeller performance are discussed in detail. In order to evaluate the performance of the optimized propeller, wind tunnel experiment of scale model based on scaling laws was carried out and the numerical results are validated to be agreed reasonably well with the two experimental data.