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Forcing and Velocity Correlations in a Vibrated Granular Monolayer

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 نشر من قبل Alexis Prevost
 تاريخ النشر 2002
  مجال البحث فيزياء
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The role of forcing on the dynamics of a vertically shaken granular monolayer is investigated. Using a flat plate, surprising negative velocity correlations are measured. A mechanism for this anti-correlation is proposed with support from both experimental results and molecular dynamics simulations. Using a rough plate, velocity correlations are positive, and the velocity distribution evolves from a gaussian at very low densities to a broader distribution at high densities. These results are interpreted as a balance between stochastic forcing, interparticle collisions, and friction with the plate.



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