Collaborative Research: Wettability Control on the Mechanics of Fracture in Granular and Porous Media

合作研究：颗粒和多孔介质断裂力学的润湿性控制

• 批准号: 1933367
• 负责人: John Dolbow
• 金额: $ 35.27万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1933367&HistoricalAwards=false
• 关键词: Collaborative; Research; Wettability; Control; Mechanics

The way that fracture networks develop in granular and porous media is a question of importance to a wide range of applications, ranging from natural gas exploration to the failure of modern fuel cells. This award will support fundamental studies of how fluid flow can drive the evolution of fracture networks in granular systems. The inquiry is supported by recent observations indicating that "wettability", a measure of attraction between the fluids and the granular media, may play a vital and previously unexplored role in governing the fracture response. Insights from this study will help scientists and engineers identify the optimal process conditions to either increase or decrease fracture growth, as desired. The development of the new experiments and models will also provide training for new doctoral students from under-represented groups, transferring the requisite skills for them to address technologically important and challenging problems in flow-induced fracture. Finally, outreach activities to under-represented minority students in the STEM area are planned as part of this effort through a novel partnership with NC-SLI. In particular, a joint MIT-Duke workshop on emerging research in civil and environmental engineering will be set up to facilitate students from these groups pursuing summer research opportunities in this area.This project is focused on the morphodynamics of hydrocapillary fracture in granular and porous media with an emphasis on the role of wettability. In particular, it concerns the response of idealized cells that are densely packed with quasi-porous media and saturated with a viscous defending fluid. Observations indicate a surprisingly strong dependence of fracture morphology on wetting properties, even at high injection rates where viscous forces dominate. The main objectives are to significantly advance the current understanding of hydrocapillary fracture, and to develop model-based simulation capabilities that are useful and predictive in this space. This will be effected through the development of an integrated suite of novel experiments and accompanying computational tools that allow emerging models of these systems to be fully explored. This joint effort will allow several open questions to be examined, such as the conditions that promote stable fracturing. A central question this project seeks to answer concerns the apparent "fracture toughness" of granular media, and how such toughness evolves as the media approaches a more conventional poroelastic solid.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.

颗粒和多孔培养基中断裂网络发展的方式对于广泛的应用是一个重要的问题，范围从天然气勘探到现代燃料电池的失败。 该奖项将支持流体流动如何推动颗粒系统中断裂网络的演变的基本研究。 最近的观察结果表明，“润湿性”是流体和颗粒培养基之间吸引人的一种吸引力的“润湿性”，可能在管理断裂反应中起着至关重要且以前没有探索的作用。 这项研究的见解将帮助科学家和工程师根据需要确定最佳过程条件，以增加或减少骨折生长。 新实验和模型的开发还将为来自代表性不足的小组的新博士生提供培训，从而转移了他们解决流动引起的骨折中具有技术重要且具有挑战性的问题的必要技能。最后，通过与NC-SLI的新型合作伙伴关系，计划为STEM地区代表性不足的少数族裔学生提供外展活动。特别是，将建立有关民用和环境工程新兴研究的联合MIT-DUKE研讨会，以促进这些小组的学生在该领域寻求夏季研究机会。该项目重点介绍了毛细血管骨折的形态动力学，以颗粒状和多孔培养基的形态动力学强调了润湿性的作用。特别是，它涉及理想化的细胞的响应，这些细胞被准培养基密集地包装，并充满粘性防御流体。观察结果表明，即使在粘性力占主导地位的高注射速率下，裂缝形态对润湿特性的依赖性令人惊讶。主要目的是显着提高当前对氢化乳头断裂的理解，并开发基于模型的模拟能力，这些功能在该空间中具有有用和预测性。这将通过开发集成的新型实验和随附的计算工具来实现，从而使这些系统的新兴模型得到充分探索。这项联合努力将允许检查几个公开问题，例如促进稳定压裂的条件。该项目试图回答的一个核心问题是颗粒状媒体的明显“断裂韧性”，以及媒体的这种韧性如何发展出更传统的孔弹性固体。这项奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力和更广泛影响的评估来通过评估来支持的，这是值得的。