Aerodynamic Optimization of Angular Airfoil for Micro-Scale Mars Airplane

This study conducts a multiobjective aerodynamic optimization of angular airfoils for application to the main wing of a micro-scale Mars airplane. The target flight condition corresponds to a Reynolds number of 1×10⁴ and a Mach number of 0.6, representative of near-surface flight on Mars. The airfoil geometry is parameterized using multiple straight-line segments, resulting in an angular airfoil defined by 11 design variables. Two-dimensional compressible Navier–Stokes simulations are performed to evaluate aerodynamic performance, and the multiobjective evolutionary algorithm CHEETAH/R is employed to simultaneously maximize lift and minimize drag under structural constraints on thickness, cross-sectional area, and pitching moment. A total of 151 non-dominated airfoil designs are obtained. Compared with the baseline triangular airfoil, the optimized airfoils exhibit higher lift coefficients, lower drag coefficients, and improved lift-to-drag ratios. All optimal designs share a concave upper surface near the leading edge, which generates a strong low-pressure region accompanied by localized flow recirculation. This flow structure enhances lift while reducing both pressure and viscous drag. The airfoil optimized for maximum lift-to-drag ratio maintains superior aerodynamic performance over a wide range of angles of attack, demonstrating robust off-design characteristics. These results indicate that angular airfoils with properly designed concave leading-edge geometry are promising candidates for efficient and structurally feasible wings for future micro-scale Mars airplanes.