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arXiv · 0906.3611

Mesoscopic lattice Boltzmann modeling of soft-glassy systems: theory and simulations

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

A multi-component lattice Boltzmann model recently introduced (R. Benzi et al. Phys. Rev. Lett 102, 026002 (2009)) to describe some dynamical behaviors of soft-flowing materials is theoretically analyzed. Equilibrium and transport properties are derived within the framework of a continuum free-energy formulation, and checked against numerical simulations. Due to the competition between short-range inter-species repulsion and mid-range intra-species attraction, the model is shown to give rise to a very rich configurational dynamics of the density field, exhibiting numerous features of soft-flowing materials, such as long-time relaxation due to caging effects, enhanced viscosity and structural arrest, ageing under moderate shear and shear-thinning flow above a critical shear threshold.

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R. Benzi, M. Sbragaglia, S. Succi, M. Bernaschi, S. Chibbaro. 2009-07-30. Mesoscopic lattice Boltzmann modeling of soft-glassy systems: theory and simulations. https://doi.org/10.1063/1.3216105

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