A Research On Optimization Method Of Composite Wing

In aerospace structures, structural efficiency is an important performance index, improve theefficiency of the structure can increase the rate of the utilization rate of the materials, and reduce thestructural weight in the premise of meeting the design requirements, so as to enhance the mobility andrange of the aircraft structure and save the fuel. As an important part of the aircraft structure, the wingstructure varies, among them, wing box structure composed of two spars, ribs and stiffened panels iswidely used, its structural optimization design is coursing more and more attention in aerospace field.There are different kinds of failure modes of wings, in the process of wing structure optimization,people need to formulate corresponding design guidelines to each failure mode, and there’reconnections and contractions between each design guidelines; for the composite wing structure,there’re even more design variables, not only should the structure layout be considered, but also theinfluence of the layer thickness and the ply sequence, both continuous and discrete variables exist, allthe above result in the difficulty of the solution of wing structural optimization.Aiming at the optimization design of the wing structure, this paper presents a comprehensiveoptimization method of composite wing structure. Firstly, to ensure the calculation accuracy of thismethod, the critical coefficients in the instability calculation formula are modified through theanalysis of stiffened wing box structure instability characteristics; and then consider the criticalfactors which influence the structure strength, stiffness and stability, discuss the relationship betweeneach failure mode, using a method of grading optimization, perform static strength optimization andlayout optimization successively, to coordinate the contraction between strength and stiffness,together with the contraction between different instability modes; by quantifying the efficiency of thestructure, calculate the structural efficiency; then establish the finite element model to verify thecalculation results, through the iteration of the optimization process, eventually determine the size ofthe layout of the wing structure, coordinate the contraction of stiffness and stability, complete thecomprehensive optimization; finally, verify the correctness of the method under different load cases.