Crumple Dynamics and Interactions Mediating Elastic Deformations of Structures

调节结构弹性变形的压皱动力学和相互作用

• 批准号: 2210797
• 负责人: James Hanna
• 金额: $ 44.72万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2210797&HistoricalAwards=false
• 关键词: Crumple; Dynamics; Interactions; Mediating; Elastic

The elastic deformation of thin plate and shell structures at many length scales, from cell membranes to clothing to aircraft panels to storage tanks, is characterized by the localization of stretching and bending. This is often simply called “crumpling”, and the small regions of large deformations “crumples”. Crumples are observed to play an important role in enabling the large-scale deformations of thin structures, often through rapid transient dynamic behavior that is currently not well documented or understood. This award will facilitate the study of these fundamental deformation processes through experiments on a simple model system and two different theoretical approaches. Insights from this work will aid in the modeling and control of complex phenomena in multi-scale elastic systems that are prohibitively complex to simulate in real time through the development of reduced-order models, e.g., the aero-thermo-elastic phenomena in aerospace applications. Results will also be applicable to other branches of structural mechanics, compliant mechanisms, soft robotics, and some biological systems. The award will support a postdoctoral researcher and train a group of graduate and undergraduate students in advanced structural mechanics, with the latter involving international exchanges with collaborators. The PI and students will also co-develop an education module for a summer science and engineering program for young women in local middle and high schools.The objective of this award is to quantify and model the meso-scale mechanics of localized elastic regions (crumples) in deforming plates, focusing on the role these localized crumples play in mediating global deformations through both quasistatic and rapid transient dynamics. The work builds on preliminary experiments demonstrating phenomena such as sequences of ordered patterns, nucleation of individual crumples, and crumple-crumple or crumple-boundary interactions. Two theoretical approaches will be employed. One will leverage ideas from structural mechanics and pattern-forming systems, where “snaking” transitions occur between localized patterns in continua. Another will take a novel particle-level description of crumples as individual discrete entities that can interact with a background curvature field, with each other, and with boundaries. These approaches will be accompanied by quantitative experimental measurements of forces on, and curvatures of, buckled sheets.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

薄板壳结构在许多长度尺度上的弹性变形，从细胞膜到服装到飞机面板到储罐，其特征是拉伸和弯曲的局部化。这通常被简单地称为“皱缩”，而大变形的小区域则被称为“皱缩”。人们观察到褶皱在薄结构的大规模变形中起着重要作用，通常是通过目前没有很好记录或理解的快速瞬态动态行为。该奖项将通过在简单模型系统和两种不同理论方法上的实验，促进对这些基本变形过程的研究。这项工作的见解将有助于建模和控制多尺度弹性系统中的复杂现象，这些现象通过开发降阶模型而难以实时模拟，例如航空航天应用中的气动热弹性现象。结果也将适用于结构力学，柔性机构，软机器人和一些生物系统的其他分支。该奖项将支持一名博士后研究人员，并培养一批高级结构力学的研究生和本科生，后者涉及与合作者的国际交流。PI和学生们还将共同开发针对当地初中和高中年轻女性的暑期科学和工程课程的教育模块。该奖项的目标是量化和模拟变形板块中局部弹性区域（皱褶）的中尺度力学，重点关注这些局部皱褶在准静态和快速瞬态动力学中介导全局变形中的作用。这项工作建立在初步实验的基础上，展示了有序模式的序列、单个褶皱的成核、褶皱-褶皱或褶皱-边界相互作用等现象。我们将采用两种理论方法。一个将利用结构力学和模式形成系统的思想，其中“蛇形”转换发生在连续的局部模式之间。另一种将采用一种新颖的粒子级描述，将皱褶描述为可以与背景曲率场、彼此之间以及与边界相互作用的个体离散实体。这些方法将伴随着对屈曲板的力和曲率的定量实验测量。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。