Velocity fluctuations and hydrodynamic diffusion in sedimentation
The Abdus Salam International Centre for Theoretical
Physics (ICTP) P.O. Box 586, 34100 Trieste, Italy
Accepted: 23 January 2001
We study non-equilibrium velocity fluctuations in a model for the sedimentation of non-Brownian particles experiencing long-range hydrodynamic interactions. The complex behavior of these fluctuations, the outcome of the collective dynamics of the particles, exhibits many of the features observed in sedimentation experiments. In addition, our model predicts a final relaxation to an anisotropic (hydrodynamic) diffusive state that could be observed in experiments performed over longer time ranges.
PACS: 45.70.Qj – Pattern formation / 05.40.-a – Fluctuation phenomena, random processes, noise, and Brownian motion / 82.70.Kj – Emulsions and suspensions
© EDP Sciences, 2001