Collaborative Research: Dynamics of Snapping of Tethers

合作研究：系绳折断动力学

• 批准号: 2310665
• 负责人: James Hanna
• 金额: $ 20.25万
• 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: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2310665&HistoricalAwards=false
• 关键词: Collaborative; Research; Dynamics; Snapping; Tethers

This grant will fund research that enables accurate design for performance, reliability, and safety of flexible ropes used in parachutes, mooring lines, towing cables, safety harnesses, and energy harvesting devices, thereby promoting the progress of science, and advancing the national prosperity. Whether free-ended or tethered to payloads, the behavior of flexible ropes in engineering applications can be properly understood only by accounting for potentially damage-inducing snapping-like dynamics whereby a slack object is suddenly pulled taut. Even mild yanking at one end of a cable can easily amplify accelerations and tensions by several orders of magnitude, as kinetic energy is focused on a small region near the cable’s other end. The temporal brevity of the snapping process and the corresponding strong spatial localization of energy may lead to structural failures but can also be a way to manipulate a payload. To allow researchers and engineers to quantify, explain, and predict snapping phenomena across a range of applications, this project will build theoretical and computational models that are informed by experimental observations and validated against physical tests. To encourage participation in STEM, an educational module on bungee jump dynamics will be developed for summer camp programs for high school students at the University of Nevada and the University of Texas at Austin.This research aims to develop the foundations of a modeling method for rapid, nonlinear, slack-taut transitions between effectively inextensible inertial motion to stretching and elastic wave generation of flexible objects, and to translate this method into efficient simulation techniques. It will accomplish these outcomes by deriving new boundary-layer asymptotics and scaling analyses that capture a sudden onset of large spatial gradients in tension and rapid exchange of kinetic energy to elastic potential energy and back again. It then builds on such techniques in the development of reduced order models and asynchronous time integrators that overcome unique numerical challenges associated with the nearly singular snapping dynamics. Finally, experiments on gravity-driven snapping will be performed to explore different regimes of behavior and to obtain data for comparison with theory and simulation.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.

这笔赠款将资助用于降落伞、系泊线、拖缆、安全带和能量收集装置的柔性绳索的性能、可靠性和安全性的精确设计的研究，促进科学进步，促进国家繁荣。无论是自由端还是系在有效载荷上，只有考虑到潜在的损坏诱导的折断动力学，即松弛的物体突然被拉紧，甚至是轻微的拉紧，才能正确理解工程应用中柔性绳索的行为。电缆一端的加速度和张力很容易放大几个数量级，因为动能集中在电缆另一端附近的一个小区域上，断裂过程的时间短暂性和相应的能量的强烈空间局部化可能会导致结构性损坏。为了让研究人员和工程师能够量化、解释和预测一系列应用中的折断现象，该项目将建立理论和计算模型，这些模型以实验观察为基础，并根据物理进行验证。测试。为了鼓励参与 STEM，我们将为内华达大学和德克萨斯大学奥斯汀分校的高中生夏令营项目开发一个关于蹦极动力学的教育模块。这项研究旨在为快速、灵活的建模方法奠定基础。有效地不可扩展的惯性运动与柔性物体的拉伸和弹性波生成之间的非线性、松紧过渡，并将该方法转化为有效的模拟技术，通过推导新的边界层渐进和捕获突然的尺度分析来实现这些结果。然后，它以此类技术为基础，开发了降阶模型和异步时间积分器，克服了与近乎奇异的捕捉动力学相关的独特数值挑战。最后，将进行重力驱动的捕捉实验，以探索不同的行为机制，并获得与理论和模拟进行比较的数据。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的评估进行评估，认为值得支持。影响审查标准。