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arXiv · 1112.0982

Dynamics of an Intruder in Dense Granular Fluids

Andrea Fiege·Matthias Grob·Annette Zippelius
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Abstract

We investigate the dynamics of an intruder pulled by a constant force in a dense two-dimensional granular fluid by means of event-driven molecular dynamics simulations. In a first step, we show how a propagating momentum front develops and compactifies the system when reflected by the boundaries. To be closer to recent experiments \cite{candelier2010journey,candelier2009creep}, we then add a frictional force acting on each particle, proportional to the particle's velocity. We show how to implement frictional motion in an event-driven simulation. This allows us to carry out extensive numerical simulations aiming at the dependence of the intruder's velocity on packing fraction and pulling force. We identify a linear relation for small and a nonlinear regime for high pulling forces and investigate the dependence of these regimes on granular temperature.

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Andrea Fiege, Matthias Grob, Annette Zippelius. 2012-02-28. Dynamics of an Intruder in Dense Granular Fluids. https://doi.org/10.1007/s10035-011-0309-9

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