Dispersion of tracer particles in a compressible flow
Abstract
The turbulent diffusion of Lagrangian tracer particles has been studied in a flow on the surface of a large tank of water and in computer simulations. The effect of flow compressibility is captured in images of particle fields. The velocity field of floating particles has a divergence, whose probability density function shows exponential tails. Also studied is the motion of pairs and triplets of particles. The mean square separation <Delta(t)^2> is fitted to the scaling form <Delta(t)^2> ~ t^alpha, and in contrast with the Richardson-Kolmogorov prediction, an extended range with a reduced scaling exponent of alpha=1.65 pm 0.1 is found. Clustering is also manifest in strongly deformed triangles spanned within triplets of tracers.
Keywords
Cite
@article{arxiv.nlin/0402031,
title = {Dispersion of tracer particles in a compressible flow},
author = {John R. Cressman and Walter I. Goldburg and Joerg Schumacher},
journal= {arXiv preprint arXiv:nlin/0402031},
year = {2009}
}
Comments
6 pages, 4 figures