Rheological properties of soft-glassy flows from hydro-kinetic simulations
1 Department of Physics and INFN, University of “Tor Vergata” - Via della Ricerca Scientifica 1, 00133 Rome, Italy
2 Istituto per le Applicazioni del Calcolo CNR - Via dei Taurini 19, 00185 Rome, Italy
Received: 13 September 2013
Accepted: 20 November 2013
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, , with the yield stress 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.
PACS: 83.60.La – Viscoplasticity; yield stress / 02.70.-c – Computational techniques; simulations / 83.10.Gr – Constitutive relations
© EPLA, 2013