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arXiv · 1506.08722

Rheology of confined non-Brownian suspensions

Walter Fornari·Luca Brandt·Pinaki Chaudhuri·Cyan Umbert Lopez·Dhrubaditya Mitra·Francesco Picano
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Abstract

We study the rheology of confined suspensions of neutrally buoyant rigid monodisperse spheres in plane-Couette flow using Direct Numerical Simulations. We find that if the width of the channel is a (small) integer multiple of the sphere's diameter, the spheres self-organize into two-dimensional layers that slide on each other and the suspension's effective viscosity is significantly reduced. Each two-dimensional layer is found to be structurally liquid-like but their dynamics is frozen in time.

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Walter Fornari, Luca Brandt, Pinaki Chaudhuri, Cyan Umbert Lopez, Dhrubaditya Mitra, Francesco Picano. 2015-06-29. Rheology of confined non-Brownian suspensions. https://doi.org/10.1103/physrevlett.116.018301

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