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Microscopic mechanism for the shear-thickening of non-Brownian suspensions

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 نشر من قبل Lucio Isa
 تاريخ النشر 2013
  مجال البحث فيزياء
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We propose a simple model, supported by contact-dynamics simulations as well as rheology and friction measurements, that links the transition from continuous to discontinuous shear-thickening in dense granular pastes to distinct lubrication regimes in the particle contacts. We identify a local Sommerfeld number that determines the transition from Newtonian to shear-thickening flows, and then show that the suspensions volume fraction and the boundary lubrication friction coefficient control the nature of the shear-thickening transition, both in simulations and experiments.



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