Practical 3d Aerodynamic Design and Optimization Using Unstructured Meshes

A methodology for performing optimization on 3D unstructured grids based on the Euler equations is presented. The same, low-memory-cost explicit relaxation algorithm is used to resolve the discrete equations which govern the ow, linearized direct and adjoint problems. The analysis scheme is a high resolution Local-Extremum-Diminishing (LED) type scheme which uses Roe decomposition for the dissipative uxes. Mesh movement is performed in such a way that optimization of arbitrary geometries is allowed. The parallelization of the algorithm, which permits its extension to optimization of realistic, complete aircraft geometries is presented. Two sample optimizations are performed. The rst is the inverse design of a transonic wing/body connguration using a surface target pressure distribution found by analyzing the geometry for known design variable deeections. The second exercise is the inverse design of a business jet connguration consisting of wing, body, strut, nacelle, horizontal n and vertical n. The surface target pressure distribution in this case is provided by an analysis of the connguration with no strut-nacelle.