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arXiv · 1709.04210

Rheology of suspensions of viscoelastic spheres: deformability as an effective volume fraction

Marco Edoardo Rosti·Luca Brandt·Dhrubaditya Mitra
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Abstract

We study suspensions of deformable (viscoelastic) spheres in a Newtonian solvent in plane Couette geometry, by means of direct numerical simulations. We find that in the limit of vanishing inertia the effective viscosity $μ$ of the suspension increases as the volume-fraction occupied by the spheres $Φ$ increases and decreases as the elastic modulus of the spheres $G$ decreases; the function $μ(Φ,G)$ collapses to an universal function, $μ(Φ_e)$, with a reduced effective volume fraction $Φ_e(Φ,G)$. Remarkably, the function $μ(Φ_e)$ is the well-known Eilers fit that describes the rheology of suspension of rigid spheres at all $Φ$. Our results suggest new ways to interpret macro-rheology of blood.

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Marco Edoardo Rosti, Luca Brandt, Dhrubaditya Mitra. 2018-01-10. Rheology of suspensions of viscoelastic spheres: deformability as an effective volume fraction. https://doi.org/10.1103/physrevfluids.3.012301

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