Shear flow effects on a critical binary mixture during phase separation

doi:10.1016/0378-4371(91)90415-9

Physica A: Statistical Mechanics and its Applications

Volume 174, Issue 1, 1 May 1991, Pages 31-46

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Abstract

The effects of a shear flow on growth during phase separation of liquids are investigated. A light scattering study is performed during the spinodal decomposition of a critical binary mixture (water-isobutyric acid) under a Couette flow. Three orthogonal planes are studied in the Fourier space. We find that even a very weak shear can markedly affect the separation process, producing both an anisotropic growth and an unexpected loss of correlation between domains in only one direction. The comparison with a numerical simulation where only the deformation is taken into account enables the flow effects to be separated from growth. In the stretching direction, a scaled function of growth that depends on temperature, time and shear rate is proposed. It is seen to fit the data well.

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Shear flow effects on a critical binary mixture during phase separation

Abstract

Ann. Phys.

Physica A

Prog. Theor. Phys.

Phys. Rev. A

Phys. Rev. A

Phys. Rev. Lett.