Collective Motion of Inelastic Particles between Two Oscillating Walls

Fei Fang Chung; Sy-Sang Liaw; Wei Chun Chang

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arXiv · 1101.5438

Collective Motion of Inelastic Particles between Two Oscillating Walls

Fei Fang Chung·Sy-Sang Liaw·Wei Chun Chang

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Abstract

This study theoretically considers the motion of N identical inelastic particles between two oscillating walls. The particles' average energy increases abruptly at certain critical filling fractions, wherein the system changes into a solid-like phase with particles clustered in their compact form. Molecular dynamics simulations of the system show that the critical filling fraction is a decreasing function of vibration amplitude independent of vibration frequency, which is consistent with previous experimental results. This study considers the entire group of particles as a giant pseudo-particle with an effective size and an effective coefficient of restitution. The N-particles system is then analytically treated as a one-particle problem. The critical filling fraction's dependence on vibration amplitude can be explained as a necessary condition for a stable resonant solution. The fluctuation to the system's mean flow energy is also studied to show the relation between the granular temperature and the system phase.

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Fei Fang Chung, Sy-Sang Liaw, Wei Chun Chang. 2011-01-28. Collective Motion of Inelastic Particles between Two Oscillating Walls. https://arxiv.org/abs/1101.5438

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