Topology Design Optimization of Stiffened Thin-wall Shell Structures Based on Growth Mechanism of Root System

DING Xiaohong¹  LIN Jianzhong¹  YAMAZAK^I  Koestu²

(1. College of Mechanical Engineering, University of Shanghai for Science and Technology, Shanghai 200093;
2. Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-1192, Japan)

Abstract: The growth mechanism of root system in nature is applied to the research of the topology design optimization technique for stiffened thin-wall shell structures. The process of the stiffener generation on a thin-wall shell structure can be regarded as a gradual growth process to achieve a global optimum by adapting to the local working condition, which is similar to the growth process of root system of plants. The design criterion of the stiffener layout on thin-wall shell structures is suggested on the basis of the growth mechanism of root system morphology, i.e., the growth direction and velocity of a stiffener are decided by its design sensitivity, which is the derivation of the strain energy with respect to its cross-sectional area in the case of the minimum compliance design problem. The numerical results of stiffened thin-wall cylindrical shell are illustrated, and validated by the finite element analysis. The suggested design method is simpler and more effective than the conventional methods, and it is more applicable to the practical problem because the result is legible distribution of the stiffeners rather than the vague density distribution. The design results can be used to the initial optimum models in the further detail design process.

Key words: Topology optimization  Bionic design  Minimum compliance  Stiffened thin-wall shell

CLC No: TH11 TB125

上海市自然科学基金(04ZR14098)和上海市教委发展基金(05EZ45)资助项目. Received 20070506, received in revised form 20071220

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