Linear viscoelastic behavior of dense hard-sphere dispersions

Structural properties of dense hard sphere packings.

We numerically study structural properties of mechanically stable packings of hard spheres (HS), in a wide range of packing fractions 0.53 ≤ ϕ ≤ 0.72. Detailed structural information is obtained from the analysis of orientational order parameters, which clearly reveals a disorder-order phase transition at the random close packing (RCP) density, ϕc ≃ 0.64. Above ϕc, the crystalline nuclei form 3...

Computer simulations of dense hard-sphere systems

We present comprehensive results of large-scale molecular dynamics and Monte Carlo simulations of systems of dense hard spheres at volume fraction f along the disordered, metastable branch of the phase diagram from the freezing-point f f to random close packing volume fc . It is shown that many previous simulations contained deficiencies caused by crystallization and finite-size effects. We qua...

Phase and rheological behavior of high-concentration colloidal hard-sphere and protein dispersions.

Colloidal hard-sphere (HS) particles of narrow-size distribution exhibit crystalline and glassy states beginning at the particle volume fractions phi = 0.494 and phi(G) = 0.58, respectively. Dynamic rheological data on the dispersions were strongly modified to solid-like behavior as phi approached phi(G). In addition, cooperative motion in structural relaxation has been observed microscopically...

Rolling friction for hard cylinder and sphere on viscoelastic solid.

We calculate the friction force acting on a hard cylinder or spherical ball rolling on a flat surface of a viscoelastic solid. The rolling-friction coefficient depends non-linearly on the normal load and the rolling velocity. For a cylinder rolling on a viscoelastic solid characterized by a single relaxation time Hunter has obtained an exact result for the rolling friction, and our result is in...

Phase Behavior of Dispersions of Hard Spherical Particles