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arXiv · 1305.2594

Rheological properties of soft-glassy flows from hydro-kinetic simulations

R. Benzi·M. Bernaschi·M. Sbragaglia·S. Succi
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Abstract

Based on numerical simulations of a lattice kinetic model for soft-glassy materials, we characterize the global rheology of a dense emulsion-like system, under three representative load conditions: Couette flow, time-oscillating Strain and Kolmogorov flow. It is found that in all cases the rheology is described by a Herschel-Bulkley (HB) relation, $σ= σ_{Y} + A S^β$, with the yield stress $σ_{Y}$ largely independent of the loading scenario. A proper rescaling of the HB parameters permits to describe heterogeneous flows with space-dependent stresses, based on the notion of cooperativity, as recently proposed to characterize the degree of non-locality of stress relaxation phenomena in soft-glassy materials.

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R. Benzi, M. Bernaschi, M. Sbragaglia, S. Succi. 2014-02-28. Rheological properties of soft-glassy flows from hydro-kinetic simulations. https://doi.org/10.1209/0295-5075%2F104%2F48006

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