These lecture notes, prepared for the 1997 VKI Lecture Course on Inverse Design, discuss the use of unstructured grid CFD methods in the design of complex aeronautical geometries. The emphasis is on gradient-based optimisation approaches. The evaluation of approximate and exact linear sensitivities is described, as are different ways of formulating the adjoint equations to greatly reduce the computational cost when dealing with large numbers of design parameters. \ud
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The current state-of-the-art is illustrated by two examples from turbomachinery and aircraft design