In the viscous transonic flow region, the crusing efficiency of aircrafts is closely related to the drag. The drag can be reduced by means of designing optimal airfoil. In general, there are two categgories in designing airfoil shapes. One is the inverse design and the other is the optimization. The method of optimization is preferred due to their easy appliance of constraints. Although they are very time-consumming. In contrast, the inverse design method are much faster than the method of optimization. However, the required target pressure distribution in this procedure is very dependent on designer's experience.
The purpose of this paper is to develop a computer code for designing the airfoil shapes, which is efficient to minimize the wave drag and the friction drag of airfoils. For this porpose, a fast and efficient design mehtod is suggested for the viscous flows. where the target pressure is obtained by optimization efficiently and the airfoil shape is determined by the inverse design.
