Design of Optimized Patches to Reinforce Damaged Wings

This paper describes the optimization process of composite patches designed to reinforce damaged wings. The main objective is to reduce the stress level in a damaged area located near the anchorage of the wing to the fuselage. Genetic algorithms are used for optimizing the ply orientations of the stacking sequence as well as the location and shape of the patch. The stress field in the structure is computed with the ANSYS finite element package. Several examples illustrate the fact that the stress flow within the wing is deviated, thus leading to a decrease of the stress level in the damaged area to be relieved.

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