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Dispersion of tracer particles in a compressible flow

John R. Cressman·Walter I. Goldburg·Joerg Schumacher
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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 is fitted to the scaling form ~ 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.

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John R. Cressman, Walter I. Goldburg, Joerg Schumacher. 2004-02-19. Dispersion of tracer particles in a compressible flow. https://doi.org/10.1209/epl%2Fi2003-10187-x

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