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arXiv · 1605.09664

Experimental observation of 1/f noise in quasi-bidimensionnal turbulent flows

Johann Herault·François Pétrélis·Stephan Fauve
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Abstract

We report the experimental observation of $1/f^α$ noise in quasi-bidimensionnal turbulence of an electromagnetically forced flow. The large scale velocity $U_L$ exhibits this power-law spectrum with $α\simeq 0.7$ over a range of frequencies smaller than both the characteristic turn-over frequency and the damping rate of the flow. By studying the statistical properties of sojourn time in each polarity of $U_L$, we demonstrate that the $1/f^α$ noise is generated by a renewal process, defined by a two-state model given by the polarities of the large scale circulation. The statistical properties of this renewal process are shown to control the value of the exponent $α$.

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Johann Herault, François Pétrélis, Stephan Fauve. 2016-05-31. Experimental observation of 1/f noise in quasi-bidimensionnal turbulent flows. https://arxiv.org/abs/1605.09664

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