Mechanic Waves in Sand: Effect of Polydispersity
نویسندگان
چکیده
The sound propagation mechanisms inside dense granular matter are challenging the attempts to describe it because of the discrete nature of the material. Phenomena like dissipation, scattering, and dispersion are hard to predict based on the material state and/or properties and vice-versa. We propose here a simulation method using dynamic discrete elements in order to get more insight in this problem. The idea is to examine a small perturbation created on one side of a dense, static packing of grains of tiny size variations as small as typical contact deformations, during its propagation and when it arrives at the opposite side. Simulations with ordered, monodisperse and polydisperse, packings, reveal a strong impact of the system on the wave properties.
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