## Kinetic characterization of non-linear soft-glassy rheology    [PDF]

R. Benzi, M. Bernaschi, M. Sbragaglia, S. Succi
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 Couette flow and Kolmogorov flow. In all cases, it is found that the rheology is described by a Herschel-Bulkley (HB) relation, $\sigma = {\sigma}_{Y} + A S^{\beta}$, with the yield stress ${\sigma}_{Y}$ largely independent of the loading scenario. Under a proper rescaling of the HB parameters, we can also describe the local rheological behavior, which turns out to be different from the global one because of the spatial heterogeneities. Our analysis illuminates the crucial role of numerical simulations in allowing a seamless exploration of different loading scenarios and enabling measurements of local energy transfer within the flowing material.
View original: http://arxiv.org/abs/1305.2594