Experimental, Theoretical and Computational Study of Compressed Thin Films Diaphragms

压缩薄膜膜片的实验、理论和计算研究阿尔贝托·M·奎蒂诺和古斯塔沃·吉奥亚机械与航天工程系，罗格斯大学皮斯卡塔韦，新泽西州08854-8058计划进行实验、理论和计算研究，以研究各向异性压缩薄膜膜片的力学。该项目的动机是实验结果表明，各向异性压缩膜片的行为与各向异性压缩膜片的行为有根本不同。因此，代替在各向同性情况下获得的良好表现的折叠图案，各向异性情况导致微结构，即缺乏与边界条件相关联的长度尺度的精细折叠图案。这些微观结构是潜在能量的旋节结构的征兆。实验工作将提供关于发生折叠微结构的应力状态范围、微结构配置与应力状态历史和横隔膜大小等因素的依赖关系以及弯曲对折叠细化的规律性影响的定量信息。理论工作将允许确定适当的能量泛函，表征相关的最小化序列，并开发设计具有适合特定目的的折叠图案的横隔膜的能力。将开发计算工具，以便与理论结果进行详细比较，并用于不符合理论处理的实际情况。

Experimental, Theoretical, and Computational Study of CompressedThin-Film DiaphragmsAlberto M. Cuitino and Gustavo Gioia Department of Mechanical & Aerospace Engineering Rutgers University Piscataway, NJ 08854-8058Experimental, theoretical, and computational research is planned tostudy the mechanics of anisotropically compressed thin film diaphragms.The project is motivated by experimental results which indicate thatthe behavior of anisotropically compressed diaphragms is fundamentally different from that of isotropically compressed ones. Thus, in lieu ofthe well-behaved folding patterns which obtain in the isotropic case,the anisotropic case leads to microstructures, i.e. fine foldingpatterns which lack a length scale associated with the boundaryconditions. These microstructures are symptomatic of the spinodalstructure of the underlying energetics.Experimental work will yield quantitative information on the range ofstress states for which folding microstructures occur, the dependence ofmicrostructure configurations on such factors as stress state historyand diaphragm size, and the regularizing effect of bending on foldingrefinement. The theoretical work will allow to determine the appropriateenergy functionals, characterize the associated minimizing sequences,and develop the capability to engineer diaphragms with folding patternssuited to specific purposes. Computational tools will be developed fordetailed comparison with theoretical results, and for use in practicalcases which are not amenable to theoretical treatment.