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arXiv · 2109.07786

Dynamics of microstructure anisotropy and rheology of soft jammed suspensions

Nicolas Cuny·Éric Bertin·Romain Mari
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Abstract

We explore the rheology predicted by a recently proposed constitutive model for jammed suspensions of soft elastic particles derived from particle-level dynamics [Cuny et al., Phys. Rev. Lett. 127, 218003 (2021)]. Our model predicts that the orientation of the anisotropy of the microstructure, governed by an interplay between advection and contact elasticity, plays a key role at yielding and in flow. It generates normal stress differences contributing significantly to the yield criterion and Trouton ratio. It gives rise to non-trivial transients such as stress overshoots in step increases of shear rate, residual stresses after flow cessation and power-law decay of the shear rate in creep. Finally, it explains the collapse of storage modulus as measured in parallel superposition for a yielded suspension.

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Nicolas Cuny, Éric Bertin, Romain Mari. 2021-09-16. Dynamics of microstructure anisotropy and rheology of soft jammed suspensions. https://doi.org/10.1039/d1sm01345a

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