Computational Studies of Fracture Networks in Particulate Systems

颗粒系统中断裂网络的计算研究

• 批准号: 1537306
• 负责人: John Dolbow
• 金额: $ 29万
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1537306&HistoricalAwards=false
• 关键词: Computational; Studies; Fracture; Networks; Particulate

This project is motivated by recent observations of evolving fracture networks in tightly-packed systems of particles, or particle rafts, interacting with fluids. Research supported by this award is focused on computational models and simulations of these systems. Simulations will enable detailed investigations into their behavior, and help to answer open questions such as why seemingly small perturbations in particle packing give rise to dramatically different fracture patterns. The tightly packed particle network is an idealized porous medium, and the injection of surfactant is what drives the growth of the fracture networks. This type of coupling between fluid flow and crack growth is central to many problems of technological relevance, including hydraulic fracturing and corrosion-assisted fracture. The tabletop experiments are simple and cost effective to study particle systems in detail. The effort involves outreach activities to public elementary schools in North Carolina, where movies of the simulations and experiments of fracture networks will be shown. These in-class demonstrations will be used as a launching point to introduce students to basic programming concepts at a young age. The research supported by this award is aimed at using simulation science to determine the influence of particle packing, size distributions, and surfactant injection on fracture evolution in particulate systems. The simulations will provide a means to consider systems beyond the practical limits of experimental testing, such as a much broader range of particle sizes and packing configurations. In the process, fundamental contributions will be made in applied mechanics and computational science. These include: 1) a chemo-poro-elasticity based theory for the fracturing of particulate raft systems; and 2) multi-scale, coupled finite-element and molecular dynamics methods that can handle a range of time-scales, from the fast scales of particle interactions to the much slower scales of surfactant diffusion. These models and simulations will be used to study recent experiments in the dynamics of fracture of particulate rafts, focusing on the important roles of particle heterogeneity and surfactant injection.

该项目的动机是由于最近观察到与流体相互作用的紧密包装系统或颗粒筏系统中不断发展的断裂网络的动机。 该奖项支持的研究集中在这些系统的计算模型和模拟上。 模拟将使对其行为进行详细的研究，并有助于回答开放问题，例如为什么粒子堆积中看似很小的扰动会导致截然不同的断裂模式。 紧密填充的粒子网络是一种理想化的多孔介质，表面活性剂的注射是驱动断裂网络生长的原因。 流体流量和裂纹生长之间的这种类型的耦合对于许多技术相关性问题（包括液压压裂和腐蚀辅助骨折）至关重要。 桌面实验详细研究粒子系统是简单且具有成本效益的。 这项工作涉及向北卡罗来纳州的公立小学进行外展活动，其中将展示裂缝网络的模拟和实验的电影。 这些课堂演示将被用作启动点，以向学生介绍年轻时的基本编程概念。 该奖项支持的研究旨在使用模拟科学来确定颗粒堆积，大小分布和表面活性剂注射对颗粒系统断裂演化的影响。 模拟将提供一种方法，以考虑超出实验测试实际限制的系统，例如粒径和包装配置的范围更广泛。 在此过程中，将在应用力学和计算科学中做出基本贡献。 其中包括：1）基于化学术的基于颗粒筏系统破裂的理论； 2）从粒子相互作用的快速尺度到表面活性剂扩散的尺度较慢，可以处理一系列时间尺度的多尺度，耦合有限元和分子动力学方法。 这些模型和模拟将用于研究颗粒筏裂缝动力学的最新实验，重点是颗粒异质性和表面活性剂注射的重要作用。