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Growth of density inhomogeneities in a flow of wave turbulence

A. M. Balk. G. Falkovich·M. S. Stepanov
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Abstract

We consider an advection of a passive scalar by a flow which is a superposition of random waves. We find that such a flow can lead to an exponential growth of the passive scalar fluctuations. We calculate the growth rate at the fourth order in wave amplitudes and find it non-zero when either both solenoidal and potential components are present in the flow or there are potential waves with the same frequencies but different wavenumbers.

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A. M. Balk. G. Falkovich, M. S. Stepanov. 2004-01-11. Growth of density inhomogeneities in a flow of wave turbulence. https://arxiv.org/abs/nlin/0401012

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