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arXiv · 1009.5311

Decorrelating a compressible turbulent flow: an experiment

Jason Larkin·Walter I. Goldburg
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Abstract

Floating particles that are initially distributed uniformly on the surface of a turbulent fluid, subsequently coagulate, until finally a steady state is reached. This being so, they manifestly form a compressible system. In this experiment, the information dimension D_1, and the Lyapunov exponents of the coagulated floaters, are measured. The trajectories and the velocity fields of the particles are captured in a sequence of rapidly acquired images. Then the velocity sequence is randomly shuffled in time to generate new trajectories. This analysis mimics the Kraichnan ensemble and yields properties of a velocity correlation function that is delta-correlated in time (but not in space). The measurements are compared with theoretical expectations and with simulations of Boffetta et al., that closely mimic the laboratory experiment reported here.

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Jason Larkin, Walter I. Goldburg. 2010-09-27. Decorrelating a compressible turbulent flow: an experiment. https://doi.org/10.1103/physreve.82.016301

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