Aerodynamic Shape Optimization Design of Rotor Airfoils Based on Control Theory

摘要

Based on the adjoint method, the aerodynamic design problems ofthe rotor airfoils in this paper has been studied. The above problem is complicated, which involves in several kinds of the design objectives with multi-constraint conditions, such as high drag divergence mach number, maximum lift coefficient at low mach number, high lift-to-drag ratio at medium mach number, low pitch moment, etc. The compressible Reynolds-averaged Navier-Stokes equations with the multigrid and preconditoned technologies are greatly developed for the above problem. The Hicks-Henne shape function is used to meet the perturbation analysis requirement of the rotor airfoil shapes. An improved transfinite interpolation algebraic method is developed to be suitable for the demands of the computational grid generation with high quality and high efficiency, in which the grid orthogonality control technology, the surface normal vector control technology and the elliptical smoothing technology are developed to greatly improve the ability of computational grid generation for the requirements of the aerodynamic optimization procedure. Some different kinds of the design cases have been done deeply, which involve the aerodynamic inverse design, the drag reduction with the given lift coefficient and geometry constraint. The result shows that the adjoint method applied to the aerodynamic design problem of rotor airfoil is sucessful and effective.