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Phase diagram of a binary mixture in a closed cavity

A. Vorobev1,*, D. Lyubimov2, and T. Lyubimova2,3

  • 1Energy and Technology Research Group, Faculty of Engineering Sciences and the Environment, University of Southampton, Southampton SO17 1BJ, United Kingdom
  • 2Perm State University, Perm 614600, Russia
  • 3Institute of Continuous Media Mechanics, Perm 614013, Russia

  • *Corresponding author: A.Vorobev@soton.ac.uk
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Phys. Rev. E 95, 022803 – Published 8 February, 2017

DOI: https://doi.org/10.1103/PhysRevE.95.022803

Abstract

Normally, the phase diagram is reported as a property of the binary mixture. We show that the phase diagram (that is, the zones of thermodynamic stability of the states of the binary mixture) is also affected by the size of the container. We investigate the thermodynamic stability of the binary mixture in a closed cavity, and identify the zone in parameters where the binary mixture is heterogeneous in equilibrium (the zone of spinodal decomposition), the zone where the mixture is always homogeneous in equilibrium, and the zone where the transition between these two states is possible (the metastable nucleation zone). In addition, we investigate the properties of the smallest single droplet that may be in equilibrium in the closed cavity (for the given average concentration, all smaller droplets would always dissolve). We show that the size of such droplets depends on the cavity's size, as ∼L1/2.

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Phys. Rev. E 95, 022803– Published 8 February, 2017
  • Received 6 October 2016

©2017 American Physical Society

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