In this paper, results are presented from the application of an open-source code, SU2, to a suite of benchmark cases defined by the AIAA Aerodynamic Design Optimisation Discussion Group. Two geometry parameterisation methods are employed, which are Hicks— Henne bump functions and Free—Form Deformation. Mesh deformation is achieved by solving linear elasticity equations. The adjoint solver within SU2 enables efficient sensitivity analysis, and gradient—based optimisation is performed using the SLSQP optimiser. The first optimisation problem studied is the drag minimisation of the NACA 0012 aerofoil in inviscid, transonic flow subject to a minimum thickness constraint. The shock wave is greatly weakened and moved downstream, achieving as much as 83% drag reduction. The second is the lift—constrained drag minimisation of the RAE 2822 aerofoil in transonic, viscous flow. The shock is eliminated, reducing drag by 38%. The NACA 0012 optimisation shows sensitivity to several numerical settings in the parameterisation approaches, whereas the RAE 2822 optimisation is insensitive to those parameter settings. The same pattern is also observed in the design variable dimensionality study. Moreover, for both two—dimensional optimisation problems, non—unique flow solutions exist on the optimised aerofoil. The third problem is the twist optimisation of a rectangular wing to minimise the induced drag at fixed lift in subsonic, inviscid flow. A nearly elliptical lift distribution is obtained using Free—Form Deformation twist parameterisation. The drag is reduced by approximately 1 count and an improved span efficiency is achieved.
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