A lattice Boltzmann model of ternary fluid mixtures

A. Lamura ¹, G. Gonnella ¹ and J. M. Yeomans ²

¹ Istituto Nazionale per la Fisica della Materia
Dipartimento di Fisica, Università di Bari
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
via Amendola 173, 70126 Bari, Italy
² Department of Physics, Theoretical Physics- 1 Keble Rd., Oxford OX1 3NP, UK

(received 15 June 1998; accepted in final form 25 November 1998)

PACS. 47.20.Ma - Interfacial instability.
PACS. 05.70.Ln - Nonequilibrium and irreversible thermodynamics.
PACS. 83.10.Lk - Multiphase flows.

Abstract:

A lattice Boltzmann model is introduced which simulates oil-water-surfactant mixtures. The model is based on a Ginzburg-Landau free energy with two scalar order parameters. Diffusive and hydrodynamic transport is included. Results are presented showing how the surfactant diffuses to the oil-water interfaces thus lowering the surface tension and leading to spontaneous emulsification. The rate of emulsification depends on the viscosity of the ternary fluid.

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