Passive fields and particles in chaotic flows

Bruno Eckhardt; Erwan Hascoet; Wolfgang Braun

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arXiv · nlin/0303004

Passive fields and particles in chaotic flows

Bruno Eckhardt·Erwan Hascoet·Wolfgang Braun

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Abstract

Two examples for the interplay between chaotic dynamics and stochastic forces within hydrodynamical systems are considered. The first case concerns the relaxation to equilibrium of a concentration field subject to both chaotic advection and molecular diffusion. The concentration field develops filamentary structures and the decay rate depends non-monotonically on the diffusion strength. The second example concerns polymers, modelled as particles with an internal degree of freedom, in a chaotic flow. The length distribution of the polymers turns out to follow a power law with an exponent that depends on the difference between Lyapunov exponent and internal relaxation rate.

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Bruno Eckhardt, Erwan Hascoet, Wolfgang Braun. 2003-03-04. Passive fields and particles in chaotic flows. https://arxiv.org/abs/nlin/0303004

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