Low Speed Airfoil Optimization Based on Evolutionary Algorithm and Composite Parameterization Method

The aerodynamic characteristic of airfoil at 2° and 8° angles of attack in Re=1×10⁶ was comprehensively optimized to improve its performance during cruising, take-off and landing. Firstly, the airfoil was preliminarily optimized by using the aerodynamic calculation software Xfoil with NACA four-digit parameterization method to reduce the optimization space and the amount of calculation. Then, the Reynolds-averaged Navier-Stokes equations were solved for precise optimization. After that, the Hicks-Henne shape function was used to perfect the details of the airfoil surface, which makes up for the lack of detail performance of NACA four-digit parameterization method. The results show that the aerodynamic performance is generally improved by more than 20% at 2° and 8° angles of attack, and a multi-objective and multi-step aerodynamic optimization method with composite parameterization is developed.