Study On Fast Design And Analysis Method For Buckling And Post-Buckling Of Wing Structure

Stability analysis is one of the most major issues of aircraft structure design. Currently Linear buckling analysis is the major analysis method of stability analysis for industry use.With the higher calculation precision and the need of lighter structure, the post-buckling strength of stiffened panel and wing box is more and more important. This paper started with engineering point of view, considering compression, shear and other load conditions and developed fast analysis and design method of buckling and post buckling load of wing structure, the advantage of which was higher precision of buckling load and shorter calculation time of post buckling load.On the buckling analysis, traditional industry method simplifies the supported edges to simple supported edges, which may lead to conservative result, and clamped supported edges, which may lead to higher result. The biggest problem of industry method is the poor calculation precision. This paper used Ritz energy method, considering the rotational restraint of stiffeners and the influence of axial compression load of stiffeners on skin local buckling, to establish an analytical model of buckling load of stiffened panel and wing box and pointed out that the flange of stiffener attached to skin had obvious influence on local buckling load and an improved method was proposed. The joint between skin and flange was considered and the formulation for single row joints and multiple row joints was developed. An analysis procedure for buckling load and buckling location was developed combined with the local buckling analysis of stiffeners, the overall buckling analysis of stiffened panel and torsion buckling analysis of stiffeners. Analytical results showed that the precision of buckling load was much higher than traditional industry method For the further use, the buckling load of stiffened panel of wing box could be analyzed considering the Poisson effect and participated skin problem. Analytical results had good agreement with FEM results.On the post buckling analysis, a local analytical model of flange-skin region was developed and could be used to calculate the debond load combined with the effective width method. An analysis procedure was proposed for buckling and post buckling load of stiffened panel, which could improve the efficiency and could be used in preliminary design.