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arXiv · 1505.01355

Non-equilibrium concentration fluctuations in binary liquids with realistic boundary conditions

J. M. Ortiz de Zarate·T. R. Kirkpatrick·J. V. Sengers
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Abstract

Because of the spatially long-ranged nature of spontaneous fluctuations in thermal non-equilibrium systems, they are affected by boundary conditions for the fluctuating hydrodynamic variables. In this paper we consider a liquid mixture between two rigid and impervious plates with a stationary concentration gradient resulting from a temperature gradient through the Soret effect. For liquid mixtures with a large Lewis number, we are able to obtain explicit analytical expressions for the intensity of the non-equilibrium concentration fluctuations as a function of the frequency $ω$ and the wave number $q$ of the fluctuations. In addition we elucidate the spatial dependence of the intensity of the non-equilibrium fluctuations responsible for a non-equilibrium Casimir effect.

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BibTeXRIS

J. M. Ortiz de Zarate, T. R. Kirkpatrick, J. V. Sengers. 2015-09-18. Non-equilibrium concentration fluctuations in binary liquids with realistic boundary conditions. https://doi.org/10.1140/epje%2Fi2015-15099-x

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