Study On The Multi-level Optimization Design Based On Shape Optimization

Multi-level optimization technique is an important method, which decomposes a complex optimum problem into a set of simplex optimization problems to be easily solved. Use of multi-level optimization technique in structural optimization design can reduce the structural weight, improve the efficiency of calculation, and shorten the design cycles. Multi-level optimization design based on the multi-level optimization technique and shape optimization method is researched in this thesis.The purpose, significance and source of the project are introduced in this thesis. The development history and the state-of-the-arts about the structural optimum design and multi-level optimum technique are surveyed. The concept and the main approaches of the shape optimization are introduced, and the research in this thesis is also presented. The object-oriented finite element program is studied. The object-oriented technique is applied to the multi-level optimization design to develop out the multi-level optimization design program. The multi-level modeling of the structural optimum problems is also discussed in this thesis .The multi-level optimum method for the planar elastic structures are given. Combined with the iSight software and the multi-level optimum technique a multi-level optimum design system for the planar elastic structures is established. The research results on the standard examples show that the method is valid and rational.