【作者】 张鹏；

【导师】 关振群；

【作者基本信息】 大连理工大学 ， 工程力学， 2006， 硕士

【摘要】 工程系统的设计常常面临多学科的严峻挑战,复杂产品的开发涉及多个学科领域,因此,在传统优化的基础上,针对复杂工程系统的多学科设计优化应运而生,它可以缩短开发时间、降低产品成本、提高产品质量。 现有的敏捷制造方法,在设计过程中都不考虑后期的优化过程,导致优化设计与初始设计不同步,协同程度低。而在大型机械系统中,各部门之间优化目标耦合严重,各设计单元之间的不协同更是严重的影响了设计系统的合理性和快捷性。 本文基于新一代的协同优化平台Workbench及参数化建模平台Solidworks,PRO/E,以及目前应用最为广泛地CAE分析平台ANSYS,CFX5.7.1,将参数化建模与有限元分析优化系统紧密集成,克服了以往CAD设计与CAE分析的不同步的弱点;实现了不同设计部门多学科协同设计,能够极大的提高优化设计在产品设计中起到的作用,特别是显著的缩短了产品的开发周期。另外,针对不确定性下的设计优化问题,通过分析不确定性的来源、建模和分析方法,改变了传统方法通过采用安全系数来处理随即因素,克服了超余量设计。通过随机模型和概率分析处理不确定性和随机性。 本文针对目前医用力学上研究比较广泛的心血管支架,通过对其多目标,高可靠性的仿真优化计算,提出了一种全新的结构模式。结果表明,本文所提出的方法协同效率高,易于实现,为机械产品的CAD/CAE一体化分析与优化设计提供了新的途径。更多还原

【Abstract】 Design for engineering system is often confronted with multidisciplinary aysterity challenge due to involving multiple disciplines for exploiting complex products, such as aerocraft, automobile,whose system design is complicate and time consuming, high cost. Hence, multidisciplinary design optimization, aimed to complex engineering system, is emerged as the times require on the basis of design optimization, which can shorten development time, reduce product cost and raise quality. Almost every practical engineering problem contains some random factors which can lead to random fluctuation, such as loading condition, material characteristics, accuracy of simulation models, geometrical feature, manufacturing tolerance and service condition. Under a multidisciplinary design environment, the uncertainties of one discipline may be propagated to another discipline through the linking variables and the final output from the intefrated multidisciplinary system has an accumulation of the uncertainties from the individual disciplines. Uncertainty will affect ultimately performance if it is not handled well. Therefore, typical MDO not only searches the best collaboration between system optimization and subsystems optimization, but also considers uncertainty leading to impact for design process and results.Based on the Multidisciplinary Design Optimization Environment WorkBench, a new method is presented for Agile optimization design of the mechanical structures. The Agile design technique which is considered as one of the most important key techniques developed/developing in these years in CAD system, the finite elements optimization system are integrated together, so that the software system developed can be used for multidisciplinary design optimization. The method evidently abridges the development periods of mechanical structures with passing over parameters in CAE system. Simultaneity, different from traditionaldesign methods in which safety factor is use to handle with random factors so that it leads to excessive design and can’t describe the impact of all kinds of random factors as well as actual safety margin, uncertainty and randomness can be dealed with by stochastic model and probability analysis with the development of quality engineering. When these techniques are applied in the framework of optimization design, they can search feasible design plan.Numerical examples of Palmaz-Schatzare stents are given to demonstrate the validity and efficiency of the technique developed.更多还原