Abstract: Ensuring the stability of the composite skin is of great significance in the design of aircraft wing structures. Theoretically, it is very difficult to solve the stability of wing structures. Therefore, a simple and reliable empirical formula, which is a simplified method by analogizing with the theoretical analysis, is adopted in engineering design. At present, the multi-spar structure is widely used in aircraft wing structures. When a multi-spar structure is designed, the focus is to reduce the structural weight through the optimal arrangement of the load-carrying components within the wing-box structures and the minimal thickness of the skin under a specified air-loading condition. The layout of the wing spars and the thickness of the skin have great effect on the stability of the composite skin. Therefore, a mathematical model on the layout optimization of wing structures is developed with the constraint of the stability of the composite skin. To solve this optimization problem, the stability of the composite skin is solved based on the empirical formula, and a sensitivity formula is also established. Finally, a wing box structure is taken as an example, and the optimal results prove that the method presented in this article is very effective in aircraft wing design.

Key words: wing structure, layout optimization, stability, composite materials, optimization design