Collaborative Research: Discontinuous shear thickening and shear jamming in dense suspensions: statistical mechanics and the microscopic basis for extreme transitions of properties

合作研究：稠密悬浮液中的不连续剪切增稠和剪切干扰：统计力学和性能极端转变的微观基础

• 批准号: 1916877
• 负责人: Bulbul Chakraborty
• 金额: $ 29.12万
• 依托单位: Brandeis 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: 2019-08-01 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1916877&HistoricalAwards=false
• 关键词: Collaborative; Research; Discontinuous; shear; thickening

Materials formed from particles are often handled in the fluid state, such as cement and concrete. These particle-laden fluids have complex flow properties, and understanding the basis for this behavior is critical to design and control of the particle interactions that are responsible for the properties. The surface interactions are also the controlling factor in the behavior of liquid-saturated soils. In the geotechnical context, controlling the interactions is not feasible, but understanding and predicting behavior is especially important. This project seeks to explain the behavior of flowing materials that exhibit very strong property changes. The focus is on suspensions with a high concentration of solid particles in a liquid. These materials often shear thicken, meaning drastically increase their viscosity, such as in cornstarch suspensions in water. This project will use simulation and theoretical methods to examine how the particle forces and surface shape cause shear thickening. Computer simulation models the forces of interaction between the particles and solves for their motion. From the forces and the particle velocities, the flow properties such as the viscosity can be determined, and these are validated against experiments. A set of theoretical tools is applied to describe the forces in the material and how they are connected in a network, much like the connections in a fishnet. The overall goal of the project is to establish a theoretical framework allowing prediction of the flow properties from a knowledge of the basic forces, thus allowing better design in engineering contexts and prediction in geophysical contexts. The team will work with industrial partners in the cement and concrete sector to use the understanding toward design of additives that modify flow behavior while retaining desired properties in the flowing and solid material. Using discrete-particle simulation and statistical mechanical theory, the goal of this project is to develop a statistical mechanical framework that describes the basis for shear thickening and jamming in highly-concentrated suspensions of solid particles in liquids. The contributions of this work will advance the statistical mechanical framework for nonequilibrium suspensions, allowing better ability to predict behavior at the macroscopic scale from a knowledge of the particle interactions. A simulation tool in its established and validated form will be used to explore the nonequilibrium steady states (NESS) ensemble of shear-thickening suspensions under constraints on stress, shear rate, and volume fraction. The ensemble data from simulation will be explored by several theoretical tools, including network theory to establish a structure-property framework appropriate for dense suspensions that approach the jamming condition. A machine learning approach will be applied to advance methods previously developed by the team for prediction of the probability of the stress state based on the microscopic force interactions. Methods from large deviation theory will be used as a framework for describing the fluctuations of properties in NESS ensemble. The simulation method will also be advanced by systematically considering the role of size distribution and particle surface complexity. In addition to simple shear, oscillatory shearing and more complex flow protocols, in which an orthogonal oscillatory component is superimposed on simple shear, will be developed and the results explored by the noted theoretical tools. The research will engage undergraduate, graduate and post-doctoral researchers. The team will prepare technical society short courses and engage in STEM outreach to expose materials physics to K-12 students.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.

由颗粒形成的材料通常以流体状态处理，例如水泥和混凝土。这些充满颗粒的流体具有复杂的流动特性，了解这种行为的基础对于设计和控制产生这些特性的颗粒相互作用至关重要。表面相互作用也是液体饱和土的控制因素。在岩土工程的背景下，控制相互作用是不可行的，但理解和预测行为是特别重要的。这个项目试图解释流动材料表现出非常强烈的性质变化的行为。重点是液体中含有高浓度固体颗粒的悬浮液。这些材料通常会发生剪切变稠，这意味着它们的粘度会急剧增加，比如玉米淀粉在水中的悬浮液。该项目将使用模拟和理论方法来研究粒子力和表面形状如何引起剪切增厚。计算机模拟了粒子之间相互作用的力，并求解了它们的运动。从力和颗粒速度可以确定流动特性，如粘度，并通过实验验证。一套理论工具被应用于描述材料中的力以及它们如何在网络中连接，就像渔网中的连接一样。该项目的总体目标是建立一个理论框架，通过对基本力的了解来预测流体特性，从而在工程环境中进行更好的设计，并在地球物理环境中进行预测。该团队将与水泥和混凝土行业的工业合作伙伴合作，利用对添加剂的理解来设计改变流动行为的添加剂，同时保持流动和固体材料的预期性能。利用离散颗粒模拟和统计力学理论，本项目的目标是开发一个统计力学框架，描述在液体中高浓度固体颗粒悬浮液中剪切增稠和堵塞的基础。这项工作的贡献将推进非平衡悬浮液的统计力学框架，使人们能够更好地从粒子相互作用的知识中预测宏观尺度上的行为。在其建立和验证形式的模拟工具将用于探索剪切-增稠悬浮液在应力、剪切速率和体积分数约束下的非平衡稳态（NESS）系综。来自模拟的集成数据将通过几种理论工具进行探索，包括网络理论，以建立适合于接近干扰条件的密集悬架的结构-性能框架。机器学习方法将应用于团队先前开发的基于微观力相互作用预测应力状态概率的方法。大偏差理论的方法将被用作描述NESS系综性质波动的框架。系统地考虑颗粒尺寸分布和颗粒表面复杂性的作用，提出了模拟方法。除了简单剪切外，振荡剪切和更复杂的流动协议，其中正交振荡分量叠加在简单剪切上，将被开发并通过著名的理论工具探索结果。这项研究将吸引本科生、研究生和博士后研究人员。该团队将准备技术学会短期课程，并参与STEM外展活动，向K-12学生展示材料物理。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Scaling Analysis of Shear Thickening Suspensions

剪切增稠悬浮液的结垢分析

• DOI: 10.3389/fphy.2022.946221
• 发表时间: 2022
• 期刊: Frontiers in Physics
• 影响因子: 3.1
• 作者: Malbranche, Nelya;Santra, Aritra;Chakraborty, Bulbul;Morris, Jeffrey F.
• 通讯作者: Morris, Jeffrey F.

K -core analysis of shear-thickening suspensions

剪切增稠悬浮液的 K 核分析

• DOI: 10.1103/physrevfluids.7.024304
• 发表时间: 2022
• 期刊: Physical Review Fluids
• 影响因子: 2.7
• 作者: Sedes, Omer;Makse, Hernan A.;Chakraborty, Bulbul;Morris, Jeffrey F.
• 通讯作者: Morris, Jeffrey F.

Ultrastable Shear-Jammed Granular Material

• DOI: 10.1103/physrevx.12.031021
• 发表时间: 2021-05
• 期刊: Physical Review X
• 影响因子: 12.5
• 作者: Yiqiu Zhao;Yuchen Zhao;Dong Wang;Hu Zheng;B. Chakraborty;J. Socolar

Shear thickening in dense bidisperse suspensions

致密双分散悬浮液中的剪切增稠

• DOI: 10.1122/8.0000495
• 发表时间: 2023
• 期刊: Journal of Rheology
• 影响因子: 3.3
• 作者: Malbranche, Nelya;Chakraborty, Bulbul;Morris, Jeffrey F.
• 通讯作者: Morris, Jeffrey F.

Investigating the nature of discontinuous shear thickening: Beyond a mean-field description

研究不连续剪切增厚的性质：超越平均场描述

• DOI: 10.1122/1.5132317
• 发表时间: 2020
• 期刊: Journal of Rheology
• 影响因子: 3.3
• 作者: E. Thomas, Jetin;Goyal, Abhay;Singh Bedi, Deshpreet;Singh, Abhinendra;Del Gado, Emanuela;Chakraborty, Bulbul
• 通讯作者: Chakraborty, Bulbul