Collaborative Proposal: Rheology and Flow of Geometrically Cohesive Granular Materials

合作提案：几何粘性颗粒材料的流变学和流动

• 批准号: 1133722
• 负责人: Scott Franklin
• 金额: $ 19.47万
• 依托单位: Rochester Institute of Tech
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1133722&HistoricalAwards=false
• 关键词: Collaborative; Proposal; Rheology; Flow; Geometrically

1133722 PI: Franklin1133722PI: TeitelThis project investigates a class of granular materials that are geometrically cohesive, e.g. a collective pile of particles that resists tensile forces. Examples of geometrically cohesive granular materials (GCGM) include long, thin rods (e.g. haystacks) and concave-shaped particles (semi-circles or U-shaped staples). These materials present a rich opportunity for basic research as well as new practical applications where structural rigidity, lightweight, and porosity are desired.Computer simulations and experiments for a variety of particle shapes - rods, semi-circles, and U-shaped staples - will be carried out to provide a better micro and macroscopic understanding of how particle shape affects fluidization and solidification in GCGM. Experiments previously carried out to characterize spherical granular media?basic rheology, tumbling, collapse, and flow ? will be repeated for the above complex-shaped particles. Numerical simulations using the Discrete Element Method will be used to probe the particle-level mechanism by which geometric cohesion occurs. New parallelization techniques involving graphics processing units (GPUs) will be developed for simulating thousands of particles. These experimental and computational studies will be used to explore the possible universality in geometric cohesion, the scaling of critical lengths, and the fundamental mechanism by which this cohesion occurs.This work will lead to increased understanding of granular materials consisting of complex shaped particles, a common occurrence in many industrial processes. The project also initiates collaboration between two institutions: a primarily undergraduate institute, Rochester Institute of Technology, and an R1 research university, University of Rochester. The collaboration will engage undergraduate and graduate students in a rich educational experience that emphasizes communication between experimentalists and computational researchers. Simulations and table-top experiments will allow undergraduates to engage in cutting edge research at both institutions.

1133722 PI：Franklin1133722PI：Teitel 该项目研究一类具有几何粘性的颗粒材料，例如抵抗拉力的颗粒的集体堆。 几何粘性颗粒材料 (GCGM) 的示例包括长而细的棒（例如干草堆）和凹形颗粒（半圆形或 U 形钉书钉）。这些材料为基础研究以及需要结构刚性、轻质和多孔性的新实际应用提供了丰富的机会。针对各种颗粒形状（棒状、半圆形和 U 形钉）的计算机模拟和实验将进行该研究是为了更好地了解颗粒形状如何影响 GCGM 中的流化和凝固。先前进行的实验是为了表征球形颗粒介质？基本流变学、翻滚、塌陷和流动？对于上述复杂形状的颗粒将重复上述过程。使用离散元法的数值模拟将用于探讨几何内聚力发生的粒子级机制。将开发涉及图形处理单元（GPU）的新并行化技术来模拟数千个粒子。这些实验和计算研究将用于探索几何内聚力、临界长度的缩放以及这种内聚力发生的基本机制的可能普遍性。这项工作将增进对由复杂形状颗粒组成的颗粒材料的理解，在许多工业过程中常见。该项目还启动了两个机构之间的合作：一个主要是本科院校，罗彻斯特理工学院，和一个 R1 研究型大学，罗彻斯特大学。 此次合作将使本科生和研究生获得丰富的教育体验，强调实验学家和计算研究人员之间的沟通。 模拟和桌面实验将使本科生能够在两个机构从事前沿研究。