Enhancement of diffusive transport by non-equilibrium thermal fluctuations

Enhancement of Diffusive Transport by Nonequilibrium Thermal Fluctuations

We study the contribution of advection by thermal velocity fluctuations to the effective diffusion coefficient in a mixture of two identical fluids. The steady-state diffusive flux in a finite system subject to a concentration gradient is enhanced because of long-range correlations between concentration fluctuations and fluctuations of the velocity parallel to the concentration gradient. The en...

Diffusive Transport Enhanced by Thermal Velocity Fluctuations

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, whi...

Diffusive transport by thermal velocity fluctuations.

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, whi...

Thermal Fluctuations in Non-Equilibrium Thermodynamics

Thermal fluctuations in fluids and fluid mixtures in stationary nonequilibrium states are spatially long ranged. This long-ranged nature of the non-equilibrium fluctuations is caused by a coupling between hydrodynamic modes through the non-equilibrium fluxes or gradients. The phenomena are discussed with some illustrative examples in fluids and fluid mixtures.

Thermal non-equilibrium transport in colloids