Improving the Density of Jammed Disordered Packings Using Ellipsoids

@article{citeulike:2713802, abstract = {Packing problems, such as how densely objects can fill a volume, are among the most ancient and persistent problems in mathematics and science. For equal spheres, it has only recently been proved that the face-centered cubic lattice has the highest possible packing fraction [IMG]f1.gif" BORDER="0">. It is also well known that certain random (amorphous) jammed packings have {varphi} {approx} 0.64. Here, we show experimentally and with a new simulation algorithm that ellipsoids can randomly pack more densely--up to {varphi}= 0.68 to 0.71for spheroids with an aspect ratio close to that of M\&M's Candies--and even approach {varphi} {approx} 0.74 for ellipsoids with other aspect ratios. We suggest that the higher density is directly related to the higher number of degrees of freedom per particle and thus the larger number of particle contacts required to mechanically stabilize the packing. We measured the number of contacts per particle Z {approx} 10 for our spheroids, as compared to Z {approx} 6 for spheres. Our results have implications for a broad range of scientific disciplines, including the properties of granular media and ceramics, glass formation, and discrete geometry. 10.1126/science.1093010}, author = {Donev, Aleksandar and Cisse, Ibrahim and Sachs, David and Variano, Evan A. and Stillinger, Frank H. and Connelly, Robert and Torquato, Salvatore and Chaikin, P. M. }, citeulike-article-id = {2713802}, doi = {10.1126/science.1093010}, journal = {Science}, keywords = {ellipsoid, jamming, packing, science, stillinger}, month = {February}, number = {5660}, pages = {990--993}, posted-at = {2008-04-24 19:29:11}, priority = {2}, title = {Improving the Density of Jammed Disordered Packings Using Ellipsoids}, url = {http://dx.doi.org/10.1126/science.1093010}, volume = {303}, year = {2004} }

TY - JOUR ID - citeulike:2713802 L3 - citeulike-article-id:2713802 TI - Improving the Density of Jammed Disordered Packings Using Ellipsoids JF - Science VL - 303 IS - 5660 SP - 990 EP - 993 N2 - Packing problems, such as how densely objects can fill a volume, are among the most ancient and persistent problems in mathematics and science. For equal spheres, it has only recently been proved that the face-centered cubic lattice has the highest possible packing fraction [IMG]f1.gif" BORDER="0">. It is also well known that certain random (amorphous) jammed packings have {varphi} {approx} 0.64. Here, we show experimentally and with a new simulation algorithm that ellipsoids can randomly pack more densely--up to {varphi}= 0.68 to 0.71for spheroids with an aspect ratio close to that of M&M's Candies--and even approach {varphi} {approx} 0.74 for ellipsoids with other aspect ratios. We suggest that the higher density is directly related to the higher number of degrees of freedom per particle and thus the larger number of particle contacts required to mechanically stabilize the packing. We measured the number of contacts per particle Z {approx} 10 for our spheroids, as compared to Z {approx} 6 for spheres. Our results have implications for a broad range of scientific disciplines, including the properties of granular media and ceramics, glass formation, and discrete geometry. 10.1126/science.1093010 KW - ellipsoid KW - jamming KW - packing KW - science KW - stillinger AU - Donev, Aleksandar AU - Cisse, Ibrahim AU - Sachs, David AU - Variano, Evan AU - Stillinger, Frank AU - Connelly, Robert AU - Torquato, Salvatore AU - Chaikin, PM PY - 2004/02/13/ UR - http://dx.doi.org/10.1126/science.1093010 ER -