Initial nonequilibrium distribution of temperature or surfactant concentration between suspended drops and the continuous fluid in a suspension results in an unsteady-state heat/mass transfer between the phases. Nonuniformities of temperature or solute concentration, which arise as a natural result of local geometrical inhomogeneities in the suspension, produce temperature/concentration gradients along the interfaces that, in turn, generate thermocapillary fluid motion along the interfaces and migration of drops toward or apart from each other. Asymptotic analysis of the process is carried out for large Peclet numbers of the dispersed phase. The dynamics of drops is studied and the approach time is estimated for the limiting cases of small and large Peclet numbers of the continuous phase.
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