Molecular dynamics simulations of sliding friction in a dense granular material
نویسندگان
چکیده
Friction in a dense two-dimensional granular material is studied by molecular dynamics simulations. Initially the particles are ordered in a triangular lattice where the top layer feels a constant vertical pressure and horizontal velocity field. The dynamics of the material at low velocities is found to be characterized by avalanche-type motion during short time intervals followed by long stationary periods of internal stress buildup. At low external pressures, the time-averaged shear stress is found to be nearly constant for low values of the normal pressure and proportional to the load for higher pressures.
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