Optimization Design Of High Aspect Ratio Wing Structure Based On Mechanical Approximation Model

The wing is an important part of the aircraft. The wing structure design is now generally based on design history case, according to the design parameters of modified to meet the design requirements. Traditional wing design is rarely adjusted and optimized to make the structure more lightweight.In this paper, the approximate modeling method of the strength and stiffness of the wing structure is studied based on the example of a high aspect ratio wing. The optimization model,which takes the maximum structural strength as the target and the quality and stiffness index as the constraint condition, is established, and the efficient optimization algorithm is designed to optimize the wing structure.According to the concrete structure characteristics of a high aspect ratio wing,the approximate analytical model of wing mechanics is established based on the empirical formula and the theory of material mechanics in aircraft structural strength calculation, including: wing maximum stress approximation model, wing maximum deflection approximate model and wing rib torsion angle approximation model. Approximate model fully considers the original mechanical model not involving the wing beam position, rib number and sectional(inner and outer wing)wing design variables, and it provides the model of the support for the wing structure optimization design. In this paper, an approximate model is modified by the ANSYS mechanical simulation model.In order to make the wing mechanics model be able to approximate the simulation results and reduce the approximate number of design variables in the model. Through a lot of simulation experimental data analysis, the relationship between variables is constructed, and the correction factor is added. Finally, the approximate model with less unknown quantity is established and the simulation results are approximate.Based on the mechanical approximation model and the design requirements of the wing structure, the optimization model is established with the maximum strength of the wing structure as the goal, and with the quality and stiffness index as the constraint conditions. In view of the characteristics of the optimized model,the wing structure were optimized by using the improved particle swarm algorithm and genetic algorithm. Through the analysis of the adaptability of two optimization methods to solve the model, this paper gets the optimization design results based on approximation model of the wing. In this paper, the dynamic analysis of the optimized wing is carried out, and the change of the dynamic characteristics of the optimized structure is smaller than that of the front wing structure.