Jamming of bidisperse frictional spheres
Ishan Srivastava, Scott Alan Roberts, Joel Clemmer, Leonardo E. Silbert, Jeremy B. Lechman, Gary S. Grest
Abstract
By generalizing a geometric argument for frictionless spheres, a model is proposed for the jamming density J of mechanically stable packings of bidisperse, frictional spheres. The monodisperse, s -dependent jamming density mono J ( s ) is the only input required in the model, where s is the coefficient of friction. The predictions of the model are validated by robust estimates of J obtained from computer simulations of up to 10 7 particles for a wide range of s , and size ratios up to 40:1. Although J varies nonmonotonically with the volume fraction of small spheres f s for all s , its maximum value J,max at an optimal f s max are both s dependent. The optimal f s max is characterized by a sharp transition in the fraction of small rattler particles.