Optimized Airfoil Inverse Design Method Based On The Target Pressure Distribution

The design techniques of modern transonic airfoils have been the important goals of design aerodynamics, and the airfoil design methods themselves are also hoped to match the overall progress of CFD. The aerodynamic design methods are categorized into two classes simply: direct optimization methods and inverse design methods. The direct optimization methods minimize (or maximize) a given aerodynamic object function directly with the constraints gotten from the project. Such procedures, however, become extremely expensive at computation quantity. The inverse design methods solve the classical inverse problem of determining the aerodynamic shape that will produce given pressure distribution. However, they leave the users with the problem of translating the design goals into properly defined pressure distribution exhibiting the required aerodynamic characteristics. Here we have studied two classical design methods with compare, the iterative residual correction inverse design method and the genetic algorithm optimization method.Since the problem of hard to specify the target pressure distribution for the airfoils inverse design method, we try to carry out the research on combining the inverse methods and the optimization methods. A genetic algorithm has been applied to optimize target pressure distribution for inverse design methods. Pressure distributions around airfoils are parameterized and the airfoil drag is minimized under constraints on lift, airfoil thickness, and other design principles. Once target pressure distributions are obtained, corresponding airfoil geometries can be computed by an inverse design code coupled with a Navier-Stokes solver. The presented results of designed airfoil show that the method developed is feasible.