SIZE AND LAYOUT OPTIMIZAITONS OF STIFFENED SHELL UNDER AXIAL COMPRESSION
The extensive use of stiffened shells in aerospace industries is mainly motivated by the high stiffness-to-weight and strength-to-weight ratios.In this study, a bi-step optimization framework is proposed.In the first step, Smeared Stiffener Method (SSM) companied with Rayleigh-Ritz method are used to obtain the critical buckling load, instead of employing Finite Element Method (FEM) to obtain the collapse load, due to the fact that the trend of critical buckling load substantially accords with the one of collapse load.Then the size optimization is performed to find the optimum design for maximum critical buckling load under structural weight constraint using Genetic Algorithm (GA), and the design variables include skin thickness, stiffener spacing, stiffener width and height.In the second step, a stiffener spacing distribution function is used to represent the location of each circumferential stiffener along the shell length.FEM is employed to simulate the deformed shapes and collapse loads of stiffened shells with unequal spacing.The layout of circumferential stiffeners can be adjusted and optimized according to the position where collapse occurs from the FEM analysis.A 3000-mm-diameter orthogrid stiffened shell is established to demonstrate the validity of the proposed optimization framework.Results show that the collapse load of stiffened shell is improved by 13.8％, while the structural weight is decreased by 0.4％.Hence, it may be concluded that the proposed framework is suitable for the optimization of stiffened shells.
Buckling Size and Layout Optimizations Stiffened Shell Axial Compression
Bo Wang Peng Hao Gang Li Zhifeng Zhang Bin Wang Chunxiao Zhou
Dept.of Engineering Mechanics,State Key Laboratory of Structural Analysis of Industrial Equipment,Da Beijing Institute of Astronautical Systems Engineering,100076,Beijing,China
国际会议
黄山
英文
1-11
2012-06-18（万方平台首次上网日期，不代表论文的发表时间）