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Shear thickening in granular suspensions: inter-particle friction and dynamically correlated clusters

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 نشر من قبل Claus Heussinger
 تاريخ النشر 2013
  مجال البحث فيزياء
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 تأليف Claus Heussinger




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We consider the shear rheology of concentrated suspensions of non-Brownian frictional particles. The key result of our study is the emergence of a pronounced shear-thickening regime, where frictionless particles would normally undergo shear-thinning. We clarify that shear thickening in our simulations is due to enhanced energy dissipation via frictional inter-particle forces. Moreover, we evidence the formation of dynamically correlated particle-clusters of size $xi$, which contribute to shear thickening via an increase in emph{viscous} dissipation. A scaling argument gives $etasim xi^2$, which is in very good agreement with the data.



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