A new method that relies on computational fluid dynamics (CFD) and numerical optimization is used to design a transonic business jet wing. The first step of this new design method is to develop target pressures for a three-dimensional wing design using a two-dimensional airfoil optimization code (MSES-LINDOP). This airfoil optimization method is fast enough to solve a six-point design problem that is representative of an entire aircraft mission in a few minutes. A full-potential finite element code with a solution adaptive cartesian grid (TRANAIR) is used to analyze the wing-body-nacelle configuration and establish the influence of the fuselage mounted nacelles on the wing pressures. The blockage in the flow caused by these nacelles is approximated in a wing-body Euler CFD code (SYN87) with a large bump on the aft fuselage. The SYN87 code also solves an adjoint set of equations to evaluate the flowfield sensitivities in approximately the same time as that required to solve the Euler equations for one flowfield. These flowfield sensitivities enable three dimensional shape optimization in this study with a quasi-Newton optimization routine. The objective function used to design both the fuselage bump and the wing contours was a sum-of-squares of the difference between computed and target wing pressures. Finally, the surface contours are modified slightly with a computer aided drawing machine to reduce manufacturing complexity. Wind tunnel data from the Boeing transonic Wind Tunnel is in very good agreement with the pressure distributions developed for 20 deg swept wing considered in this study. This data shows that the design goals of natural laminar flow at a Mach number of 0.75 and minimum wave drag at a Mach number of 0.80 have been met and provides a validation of the design method developed in this study.

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