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arXiv · 2003.03365

Shot noise multifractal model for turbulent pseudo-dissipation

G. B. Apolinário·L. Moriconi
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Abstract

Multiplicative cascades have been used in turbulence to generate fields with multifractal statistics and long-range correlations. Examples of continuous and causal stochastic processes which generate such a random field have been carefully discussed in the literature. Here a causal lognormal stochastic process is built to represent the dynamics of pseudo-dissipation in a Lagrangian trajectory. It is introduced as the solution of a stochastic differential equation, driven by a source of noise which has sudden jumps at periodic intervals, its period being the dissipative time scale of the flow. This random field has scale invariance for a continuum of scales, and displays discontinuous jumps in time, with a smooth time evolution below the Kolmogorov scale. Its multifractal and correlation properties are demonstrated numerically.

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G. B. Apolinário, L. Moriconi. 2020-05-29. Shot noise multifractal model for turbulent pseudo-dissipation. https://doi.org/10.1088/1742-5468%2Fab9e65

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