基于应变能等效静态载荷法的热机耦合复杂结构动态响应优化机理研究

The method of traditional static optimization design was difficult to meet the urgent demand of engineering structure for dynamic performance, and dynamic constraints associated with time was difficult to deal with led to the directly dynamic optimization design may only be theory. Equivalent static loads method based on displacement was an effective way to dynamic response optimization, but had such insufficient as difficult identification of equivalent transformation time point, loading points at random, and inefficient equivalent conversion. It was only applied in the simple structure but was not efficient for the common complex structure in engineering practice.. In view of the above problem, Complex structures under thermal and mechanical load coupling dynamic response optimization mechanism research based on strain energy equivalent static loads method was proposed on the basis of identification method of equivalent conversion time points in the prophase study. Firstly, an identification theory of the key location point was proposed based on the curvature recognition of structure mode shape. Secondly, an equivalent static transformation method of kinetic model based on volume strain energy of structure was presented. Thirdly, an equivalent static transformation method of dynamic model under thermal and mechanical load coupling was proposed by comparing the two kinds of schemes for equivalent static transformation of dynamic thermal and mechanical load coupling. Finally, the method system of complex structures under thermal and mechanical load coupling dynamic response optimization mechanism research based on strain energy equivalent static loads was build. This project will lay the foundation for the engineering applications of dynamic optimization theory based on equivalent static loads method.

传统的静态优化设计已很难满足工程结构对于动态性能的迫切需求，与时间相关的动态约束难以处理导致了直接进行动态优化仅成为理论可能，位移等效静态载荷法为其提供了解决途径，但由于存在等效转化时间点识别困难、加载位置点随意、等效转化效率低等不足，仅在简单结构中得到应用，而对于工程实际中常见的复杂结构显得无能为力。.鉴于上述难题，在前期研究获得等效转化时间点识别方法的基础上，本项目拟进一步开展基于应变能等效静态载荷法的热机耦合复杂结构动态响应优化机理研究。首先，提出一种基于模态振型曲率辨识的关键位置点识别方法；其次，提出一种基于体积应变能的动力学模型等效静态转化理论；再次，通过对比研究两种动态热机耦合载荷等效静态转化方案，提出一种热机耦合结构动力学模型等效静态转化方法；最后构建基于应变能等效静态载荷法的热机耦合结构动态响应优化方法体系。本项目将为基于等效静态载荷法的动态优化理论纳入工程应用奠定基础。

传统的静态优化设计已很难满足工程结构对于动态性能的迫切需求，与时间相关的动态约束难以处理导致直接进行动态优化仅成为理论可能，位移等效静态载荷法的提出为其提供了解决途径，但存在等效转化时间点识别困难、加载位置点随意、等效转化效率低等不足，仅在简单结构中得到应用而对于工程实际中常见的复杂结构显得力不从心。.项目将结构模态振型曲率辨识理论的优势应用到关键位置点的识别方法中，提出了一种基于结构模态振型曲率辨识的关键位置点识别方法，为等效静态载荷转化提供了加载位置点；深入研究了基于体积应变能等效原理的结构动力学模型静态转化理论，通过构建基于体积应变能等效原理的结构动力学模型等效静态转化数学模型，利用全局优化算法搜索得到等效静态载荷集的最优解；利用有限元仿真计算对比分析了热机耦合结构先耦合后等效静态转化和先独立等效转化后再耦合计算的两种方案，初步探索了热机耦合动态载荷等效静态转化计算方法，最后构建了基于应变能等效静态载荷法的热机耦合复杂结构动态优化方法体系，为基于ELSM的动态响应优化理论纳入工程实践奠定了坚实基础，同时可以为结构动态响应优化设计提供新的理论指导。