Aerodynamic Characteristics Optimization Design of the HALE Joined-Wing Configuration UAV

This study investigates the factors influencing the aerodynamic performance enhancement of the rear wing of the joined-wing configuration UAVs by analyzing the flow field structure and flow mechanisms before and after airfoil optimization. Correspondingly, an optimization design concept tailored to joined-wing aircraft is proposed. Focusing on the rear wing, a three-dimensional design framework integrating geometric parameterization, aerodynamic simulation, and radar performance analysis was developed. The accuracy of the surrogate model was enhanced through multiround updating and optimization, and the optimal solution was derived using a genetic algorithm. The results demonstrate that the lift–drag ratio of the rear wing has been improved by approximately 9.7%. Specifically, the optimization outcomes confirm that adjusting the airfoil geometry and introducing a spanwise variation in the installation angle of control surfaces mitigates the adverse effects of front-wing downwash on the rear wing, thereby improving the overall aerodynamic characteristics. By fully accounting for the interference of Frt-wing downwash, this framework addresses the core challenges in rear-wing aerodynamic optimization and provides an effective solution for enhancing the high-altitude flight efficiency of UAVs.