COLLABORATIVE RESEARCH: Analysis and design of material microstructure using stochastic simulation techniques

[00:45 . 33]近年来，在诸如复合材料等先进材料的制造方面取得了巨大的进步。随着这些制造技术的进步，很明显，描述这些材料行为的模型需要改进，以便适当地引入工程设计。在许多材料中改进这些模型的一个主要障碍是微观结构水平上的高度随机性。该研究计划描述了基于模拟的方法，用于改进随机复合材料微结构的分析和设计，包括先进的纤维/颗粒复合材料、细胞/多孔材料、混凝土或其他多相材料。具体而言，研究工作将集中在以下三个方面：1)材料微观结构的概率表征；2)材料微观结构的随机模拟；3)材料行为设计问题的敏感性研究。敏感性研究将确定包裹体、体积分数等的临界尺寸和聚类模式。上述分析在复合材料工程中有两个极其重要的作用：对现有复合材料进行表征，并帮助改进和优化复合材料新应用的设计。由于所提出的技术都是基于有限元方法，因此它们可以潜在地应用于使用标准（确定性）有限元分析成功建模的任何现象，包括机械/结构系统的临界应力、应变或位移响应、一般热弹性行为、材料或几何非线性或非线性加载。这项研究是普林斯顿大学和约翰霍普金斯大学的合作成果，得到了美国国家科学基金会倡议00-26“基于模型的仿真探索性研究”的支持

0084533GrahamIn recent years, tremendous progress has been made in the fabrication of advanced materials, such as composites. As these fabrication techniques have progressed, it has become apparent that models describing behavior of these materials need improvement in order to be properly introduced into engineering design. A major obstacle in improving these models for many materials is the high degree of randomness at the microstructural level. This research plan describes simulation-based methods that address both the improved analysis and the design of random composite microstructures, including advanced fibrous/particulate composites, cellular/porous materials, concrete, or other multi-phase materials. Specifically, the proposed research work will focus on the following three areas: 1) probabilistic characterization of material microstructures, 2) stochastic simulation of material microstructures, 3) sensitivity studies of material behavior - design issues. The sensitivity studies will identify critical sizes and clustering patterns of inclusions, volume fractions, etc. The above analyses serve two extremely important roles in engineering of composite materials: to characterize existing composite materials and to aid in improving and optimizing the design of new applications of composite materials. Because the proposed techniques are all based on finite element methods, they could potentially be applied to any phenomena that have been successfully modeled using standard (deterministic) finite element analyses, including critical stress, strain, or displacement response of mechanical/structural systems, general thermoelastic behavior, material or geometric nonlinearities, or nonlinear loadings. The study is a collaborative effort between Princeton University and The Johns Hopkins University supported under NSF initiative 00-26, Exploratory Research on Model-Based Simulation.***