Airfoil optimization and aerodynamic performance analysis of a propeller for low-speed agricultural plant-protection UAVs

To overcome the limited endurance and low operating efficiency of agricultural plant-protection UAVs, this paper focuses on the propeller of a low-speed agricultural plant-protection UAV and investigates airfoil optimization and aerodynamic performance improvement. Based on blade element momentum theory, an aerodynamic model was developed. The baseline 2032C airfoil was optimized using the CST parameterization method combined with the NSGA-II multi-objective optimization algorithm, yielding the 2032YH airfoil with improved overall performance. CFD simulations were conducted to validate the model, followed by optimization of the pitch-angle distribution. Structural assessment and ground-based bench tests were subsequently performed on the optimized propeller. The results indicate that the lift-to-drag ratio of the optimized airfoil increased by about 20%. At the rated condition of 1600 r/min, the thrust of a single propeller reached 392 N, while the corresponding power was 5059.69 W, satisfying the design targets. Moreover, the structural strength and resistance to resonance of the T700 carbon-fiber composite blade met the engineering requirements. This work provides a technical reference for the efficient design of propellers for agricultural plant-protection UAVs.