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.

从细胞膜到衣服，从飞机面板到储罐，薄板和壳结构在许多长度尺度上的弹性变形的特征是局部拉伸和弯曲，这通常简称为“皱缩”，并且是局部的。据观察，大变形“褶皱”在薄结构的大规模变形中发挥着重要作用，通常是通过目前尚未得到充分记录或理解的快速瞬态动态行为。通过简单模型系统的实验和两种不同的理论方法进行的变形过程将有助于对多尺度弹性系统中的复杂现象进行建模和控制，这些系统通过简化模型的开发进行实时模拟非常复杂。该奖项将支持一名博士后研究员并培训一个团队。的毕业生和高级结构力学本科生，后者涉及与合作者的国际交流，PI 和学生还将共同开发一个针对当地初中和高中年轻女性的暑期科学与工程项目的教育模块。是对变形板中局部弹性区域（皱褶）的细观力学进行量化和建模，重点关注这些局部皱褶在通过准静态和快速瞬态动力学调节全局变形中所发挥的作用。这项工作建立在初步实验的基础上。将采用两种理论方法来演示有序图案序列、单个褶皱成核以及褶皱-褶皱或褶皱-边界相互作用等现象。另一种方法将采用一种新颖的粒子级描述，将碎石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单独离散实体。通过对弯曲板材上的力和曲率进行实验测量。该奖项反映了 NSF 的法定使命，并且通过使用基金会的智力价值和更广泛的影响审查标准进行评估，定量分析被认为值得支持。