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Pair dispersion in turbulence

G. Boffetta·A. Celani
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Abstract

We study the statistics of pair dispersion in two-dimensional turbulence. Direct numerical simulations show that the pdf of pair separations is in agreement with the Richardson prediction. The pdf of doubling times follows dimensional scaling and shows a long tail which is the signature of close approaches between particles initially seeded with a large separation. This phenomenon is related to the formation of fronts in passive scalar advection.

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G. Boffetta, A. Celani. 2001-02-20. Pair dispersion in turbulence. https://doi.org/10.1016/s0378-4371(99)00613-5

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