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arXiv · 1511.06159

Rotating turbulence under "precession-like" perturbation

Kartik P. Iyer·Irene Mazzitelli·Fabio Bonaccorso·Annick Pouquet·Luca Biferale
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Abstract

The effects of changing the orientation of the rotation axis on homogeneous turbulence is considered. We perform direct numerical simulations on a periodic box of $1024^3$ grid points, where the orientation of the rotation axis is changed (a) at a fixed time instant (b) regularly at time intervals commensurate with the rotation time scale. The former is characterized by a dominant inverse energy cascade whereas in the latter, the inverse cascade is stymied due to the recurrent changes in the rotation axis resulting in a strong forward energy transfer and large scale structures that resemble those of isotropic turbulence.

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Kartik P. Iyer, Irene Mazzitelli, Fabio Bonaccorso, Annick Pouquet, Luca Biferale. 2016-04-11. Rotating turbulence under "precession-like" perturbation. https://arxiv.org/abs/1511.06159

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