Document Type

Article

Publication Date

1-1-2011

Publication Title

Physical Review Letters

Volume

106

First Page

204501-1

Last Page

204501-4

DOI

10.1103/PhysRevLett.106.204501

Keywords

transport, fluctuations

Disciplines

Other Astrophysics and Astronomy | Other Physics

Abstract

We study the contribution of advection by thermal velocity fluctuations to the effective diffusion coefficient in a mixture of two identical fluids. We find good agreement between a simple fluctuating hydrodynamics theory and particle and finite-volume simulations. The enhancement of the diffusive transport depends on the system size L and grows as ln⁡(L/L0) in quasi-two-dimensional systems, while in three dimensions it scales as L0-1-L-1, where L0 is a reference length. Our results demonstrate that fluctuations play an important role in the hydrodynamics of small-scale systems.

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