Related Experiment Video
Updated: Aug 11, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Dynamical heterogeneity close to the jamming transition in a sheared granular material
Physical Review Letters
|February 21, 2006
Summary
This study reveals dynamic heterogeneity in dense granular packing near jamming. Grain relaxations are spatially heterogeneous and correlated, particularly during collective rearrangements.
Area of Science:
- Physics
- Materials Science
- Soft Matter Physics
Background:
- Granular materials exhibit complex dynamics near the jamming transition.
- Understanding particle rearrangements is crucial for predicting material behavior.
Purpose of the Study:
- To experimentally investigate the dynamics of bidimensional dense granular packing under cyclic shear.
- To characterize dynamic heterogeneity and correlations in granular systems near jamming.
Main Methods:
- Experimental investigation of dense granular packing under cyclic shear.
- Measurement of multipoint correlation functions, including self-intermediate and four-point correlation functions.
- Extraction of a dynamical correlation length from spatiotemporal mobility patterns.
Main Results:
- Observed slower-than-exponential relaxation in the self-intermediate scattering function, indicating dynamic heterogeneity.
- Four-point correlation functions revealed strong spatial correlations and heterogeneity in grain relaxations.
- Identified collective rearrangements occurring at specific timescales.
Conclusions:
- Experimental evidence supports dynamic heterogeneity in sheared granular systems near jamming.
- The study provides a framework for analyzing dynamic correlation functions in granular materials.
- Results pave the way for systematic studies of complex dynamics in granular media.
More Related Videos
09:00Visualization of Failure and the Associated Grain-Scale Mechanical Behavior of Granular Soils under Shear using Synchrotron X-Ray Micro-Tomography
Published on: September 29, 2019
09:08Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering
Published on: February 6, 2014
Related Concept Videos
01:20Elastic Strain Energy for Shearing Stresses
As discussed in previous lessons, strain energy in a material is the energy stored when it is elastically deformed, a concept crucial in materials science and mechanical engineering. This energy results from the internal work done against the cohesive forces within the material. When a material undergoes shearing stress and corresponding shearing strain, the strain energy density, which is the energy stored per unit volume, is calculated. Within the elastic limit, where the stress is...
01:10First Law: Particles in One-dimensional Equilibrium
Newton's first law of motion states that a body at rest remains at rest, or if in motion, remains in motion at constant velocity, unless acted on by a net external force. It also states that there must be a cause for any change in velocity (a change in either magnitude or direction) to occur. This cause is a net external force. For example, consider what happens to an object sliding along a rough horizontal surface. The object quickly grinds to a halt, due to the net force of friction. If we...
01:18First Law: Particles in Two-dimensional Equilibrium
Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
Newton's first law tells us about the...
Newton's first law tells us about the...
01:20Shearing Strain
The shearing strain represents a cubic element's angular change when subjected to shearing stress. This type of stress can transform a cube into an oblique parallelepiped without influencing normal strains. The cubic element experiences a significant transformation when exposed solely to shearing stress. Its shape alters from a perfect cube into a rhomboid, clearly demonstrating the effect of shearing strain. The degree of this strain is considered positive if it reduces the angle between the...
01:23Relation Between the Distributed Load and Shear
Understanding the relationship between the distributed load and shear force in structural analysis is crucial for analyzing beams subjected to various loading conditions. Consider the case of a beam experiencing a distributed load, two concentrated loads, and a couple moment.
02:39Phase Transitions: Melting and Freezing
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...