Aerodynamic/Stealthy Integrated Design Optimization of Airfoil for Supersonic Fighter

Abstract

Airfoil is very important in the aircraft performance. To figure out the conflicts between the requirements of the aerodynamic and stealthy design of supersonic fighter airfoil, we established a multi-objective optimization platform, which is based on high fidelity method, Parsec parameterization method, artificial neural network and Pareto genetic algorithm, to reduce the supersonic drag and radar cross section (RCS) of airfoils. Three optimized airfoils are obtained based on the optimization design. Compared with the initial airfoil, the geometric shapes of optimized airfoils have smaller leading-edge radius, later maximal thickness location and diamond-shaped thickness distribution. Reductions of the supersonic drag coefficients, the values of pitch moment and RCSs in the key azimuth of optimized airfoils are included in the design condition. Meanwhile, the lift coefficients are improved. Results also indicate that the multi-objective optimization framework could be implemented.