多学科设计优化中的不确定性建模

不确定性因素对复杂工程系统设计的影响贯穿整个设计过程.对多学科设计优化(MDO,Multidisciplinary Design Optimization)中不确定性的来源进行了总结和归类;建立了包含2个耦合学科的MDO系统分析输出结果的不确定性与设计变量输入数据误差和模型误差之间关系的数学模型,用于计算各种不确定性对系统性能的影响.算例分析结果和实验结果吻合,表明该数学模型有效可靠.经过扩展可用于估算包含多个耦合学科的MDO系统分析输出结果的不确定性,为鲁棒多学科设计优化方法的构建提供理论基础.

Uncertainty modeling in multidisciplinary design optimization

Uncertainty is pervasive throughout the design process of complex engineering system.The sources of uncertainty in multidisciplinary design optimization(MDO) were summarized and classified into three categories: requirement error,input data error and model error.A mathematical model was built up for the estimation of propagated uncertainty in MDO system that contained two coupled disciplines(subsystems),which represented the relationship between input data error,model error and uncertainty in results of MDO system analysis to evaluate the influence of uncertainties for system performance.The agreement of the final computation results with the experimental data indicates this model is effective and reliable.Having extended,this model could be used to estimate the uncertainty in results of MDO system analysis,which contains more coupled disciplines(subsystems).The research is useful for the development of robust MDO methods.