Depletion force in a bidisperse granular layer

Abstract

We demonstrate the effect of the depletion force in experiments and simulations of vertically vibrated mixtures of large and small steel spheres. The system exhibits size segregation and a large increase in the pair correlation function of the large spheres for short distances that can be accurately described using a combination of the depletion potential derived for equilibrium colloidal systems and a Boltzmann factor. The Boltzmann factor defines an effective temperature for the system, which we compare to other measures of temperature.

The effects of forcing and dissipation on phase transitions in thin granular layers

“…The interactions included in the model do not capture the full complexity of real inelastic collisions [19], but do reproduce the dominant effects of vibration, collisions, and dissipation. Furthermore, this collisional model has successfully reproduced a wide variety of phenomena that are observed in experiments, including pattern formation [20], clustering [21], rheological behavior [22], impurity segregation [23], velocity correlations [9], depletion forces [24] and phase transitions [15,16]. Moreover, simulations with this collisional model reproduce our experimental observations that ordered phases are suppressed in highly inelastic materials [17].…”

Fluctuation–dissipation: Response theory in statistical physics

“…The study of the FDR in these models is recent and has been carried out by means of numerical simulations [115][116][117][118]. Some of the numerical results has received an analytical interpretation in [119], and experimental verifications have been attempted in [120]. Other idealized models of inelastic energy exchange [121][122][123] have also been proposed.…”

Depletion forces in thin liquid films due to nonionic and ionic surfactant micelles

“…Depletion force in a bidisperse granular layer was investigated in experiments and simulations of mixtures of large and small steel spheres [12]. Sphere/wall and sphere/sphere interactions in a dilute suspension of infinitely thin rods were numerically calculated [13].…”