Non-equilibrium fluctuations induced by the Soret effect in a ternary mixture.


We present, based on fluctuating hydrodynamics, the theory of concentration fluctuations in a ternary mixture subjected to a stationary temperature gradient, so that composition gradients are present due to thermal diffusion (Soret effect). We neglect gravity and confinement (boundary conditions) but consider a completely generic diffusion matrix, including cross-diffusion effects. We find, as in the case of binary mixtures, an important non-equilibrium enhancement of the concentration fluctuations, which is proportional to the square of the gradient and inversely proportional to the fourth power of the fluctuations wave number, q(-4). The results of this paper are expected to be asymptotically correct for fluctuations of large q, while for shorter q gravity and confinement effects need to be incorporated. Comparison with previous work in the topic is included.

DOI: 10.1140/epje/i2014-14077-2

Cite this paper

@article{Zrate2014NonequilibriumFI, title={Non-equilibrium fluctuations induced by the Soret effect in a ternary mixture.}, author={Jos{\'e} Mar{\'i}a Ortiz de Z{\'a}rate and C{\'e}dric Giraudet and Henri Bataller and Fabrizio Croccolo}, journal={The European physical journal. E, Soft matter}, year={2014}, volume={37 8}, pages={34} }