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Projected free energies for polydisperse phase equilibria

Peter Sollich·Michael E Cates
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Abstract

A `polydisperse' system has an infinite number of conserved densities. We give a rational procedure for projecting its infinite-dimensional free energy surface onto a subspace comprising a finite number of linear combinations of densities (`moments'), in which the phase behavior is then found as usual. If the excess free energy of the system depends only on the moments used, exact cloud, shadow and spinodal curves result; two- and multi-phase regions are approximate, but refinable indefinitely by adding extra moments. The approach is computationally robust and gives new geometrical insights into the thermodynamics of polydispersity.

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Peter Sollich, Michael E Cates. 1997-11-28. Projected free energies for polydisperse phase equilibria. https://doi.org/10.1103/physrevlett.80.1365

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