The emergence of supramolecular forces from lattice kinetic models of non-ideal fluids: applications to the rheology of soft glassy materials

Abstract

A systematic study for a single-species lattice Boltzmann model with frustrated-short range attractive and mid/long-range repulsive-interactions is presented. The equilibrium analysis, carried out along the guidelines proposed by [X. Shan, Phys. Rev. E: Stat., Nonlinear, Soft Matter Phys., 2008, 77, 066702], allows us to determine the surface tension density and the resulting disjoining pressure developing in a thin film when two interfaces overlap. Numerical simulations of confined flows are then performed with a multicomponent model and successfully tested against a recent suggestion, motivated by experimental facts, on the existence of a cooperative length underlying the non-local rheology of highly confined soft-glassy materials [Goyon et al., Nature, 2008, 454, 8487; Goyon et al., Soft Matter, 2010, 6, 2668–2678].