Measurement of Forces Inside a Three-Dimensional Pile of Frictionless Droplets

@article{zhou06, abstract = {We present systematic and detailed measurements of interparticle contact forces inside three-dimensional piles of frictionless liquid droplets. We measured long-range chainlike correlations of the directions and magnitudes of large forces, thereby establishing the presence of force chains in three dimensions. Our correlation definition provides a chain persistence length of 10 mean droplet diameters, decreasing as load is applied to the pile. We also measured the angles between contacts and showed that the chainlike arrangement arises from the balance of forces. Moreover, we found that piles whose height was comparable to the chain persistence length exhibited substantially greater strain hardening than did tall piles, which we attributed to the force chains. Together, the results establish a connection between the microscopic force network and the elastic response of meso- or macroscopic granular piles. The conclusions drawn here should be relevant in jammed systems generally, including concentrated emulsions and piles of sand or other heavy particles. 10.1126/science.1125151}, author = {Zhou, J. and Long, S. and Wang, Q. and Dinsmore, A. D. }, citeulike-article-id = {2186364}, doi = {10.1126/science.1125151}, journal = {Science}, keywords = {confocal, emulsion, force-chain, journal-club}, month = {June}, number = {5780}, pages = {1631--1633}, posted-at = {2008-05-14 14:59:34}, priority = {0}, title = {Measurement of Forces Inside a Three-Dimensional Pile of Frictionless Droplets}, url = {http://dx.doi.org/10.1126/science.1125151}, volume = {312}, year = {2006} }

TY - JOUR ID - zhou06 L3 - citeulike-article-id:2186364 TI - Measurement of Forces Inside a Three-Dimensional Pile of Frictionless Droplets JF - Science VL - 312 IS - 5780 SP - 1631 EP - 1633 N2 - We present systematic and detailed measurements of interparticle contact forces inside three-dimensional piles of frictionless liquid droplets. We measured long-range chainlike correlations of the directions and magnitudes of large forces, thereby establishing the presence of force chains in three dimensions. Our correlation definition provides a chain persistence length of 10 mean droplet diameters, decreasing as load is applied to the pile. We also measured the angles between contacts and showed that the chainlike arrangement arises from the balance of forces. Moreover, we found that piles whose height was comparable to the chain persistence length exhibited substantially greater strain hardening than did tall piles, which we attributed to the force chains. Together, the results establish a connection between the microscopic force network and the elastic response of meso- or macroscopic granular piles. The conclusions drawn here should be relevant in jammed systems generally, including concentrated emulsions and piles of sand or other heavy particles. 10.1126/science.1125151 KW - confocal KW - emulsion KW - force-chain KW - journal-club AU - Zhou, J AU - Long, S AU - Wang, Q AU - Dinsmore, AD PY - 2006/06/16/ UR - http://dx.doi.org/10.1126/science.1125151 ER -