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Signatures of two-dimensionalisation of 3D turbulence in presence of rotation

Sagar Chakraborty
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Abstract

A reason has been given for the inverse energy cascade in the two-dimensionalised rapidly rotating 3D incompressible turbulence. For such system, literature shows a possibility of the exponent of wavenumber in the energy spectrum's relation to lie between -2 and -3. We argue the existence of a more strict range of -2 to -7/3 for the exponent in the case of rapidly rotating turbulence which is in accordance with the recent experiments. Also, a rigorous derivation for the two point third order structure function has been provided helping one to argue that even with slow rotation one gets, though dominated, a spectrum with the exponent -2.87, thereby hinting at the initiation of the two-dimensionalisation effect with rotation.

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Sagar Chakraborty. 2007-04-25. Signatures of two-dimensionalisation of 3D turbulence in presence of rotation. https://doi.org/10.1209/0295-5075/79/14002

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