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arXiv · 1404.7181

Shear thickening of highly viscous granular suspensions

Qin Xu·Sayantan Majumdar·Eric Brown·Heinrich M. Jaeger
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Abstract

We experimentally investigate shear thickening in dense granular suspensions under oscillatory shear. Directly imaging the suspension-air interface, we observe dilation beyond a critical strain $γ_c$ and the end of shear thickening as the maximum confining stress is reached and the contact line moves. Analyzing the shear profile, we extract the viscosity contributions due to hydrodynamics $η_μ$, dilation $η_c$ and sedimentation $η_g$. While $η_g$ governs the shear thinning regime, $η_μ$ and $η_c$ together determine the shear thickening behavior. As the suspending liquid's viscosity varies from 10 to 1000 cst, $η_μ$ is found to compete with $η_c$ and soften the discontinuous nature of shear thickening.

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Qin Xu, Sayantan Majumdar, Eric Brown, Heinrich M. Jaeger. 2014-04-28. Shear thickening of highly viscous granular suspensions. https://doi.org/10.1209/0295-5075%2F107%2F68004

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