抄録
The theoretical method is first introduced for clarifying the quality and level of the optimized results, obtained by using genetic algorithms (GAs) and evolutional strategies (ESs). The method includes the quasi-intuition, instinct, and plasticity. We apply this method to the problems minimizing the drag force of airfoil. Drag forces are obtained by the numerical calculation code of two-dimensional flows including an instability theory on the transition to turbulence in the boundary layer. It should be stressed that GAs and ESs are relatively easy to get the best-adapted solution for subsonic flow problems. Finally, we will discuss the robustness of the optimized airfoil shapes for small disturbances such as the attachment of insect on airfoil.
