Mean-field and fluctuation analyses of a forced turbulence simulated by the lattice Boltzmann method

W. Sakikawa; O. Narikiyo

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arXiv · cond-mat/0307604

Mean-field and fluctuation analyses of a forced turbulence simulated by the lattice Boltzmann method

W. Sakikawa·O. Narikiyo

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Abstract

On the basis of the lattice Boltzmann method we have done a numerical experiment of a forced turbulence in real space and time. Our new findings are summarized into two points. First in the analysis of the mean-field behavior of the velocity field using the exit-time statistics we have verified Kolmogorov's scaling and Taylor's hypothesis for the first time in the simulation for the Navier-Stokes equation. Second in the analysis of the intermittent velocity fluctuations using a non-equilibrium probability distribution function and the wavelet denoising we have clarified that the coherent vortices sustain the power-law velocity correlation in the non-equilibrium state.

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W. Sakikawa, O. Narikiyo. 2003-07-24. Mean-field and fluctuation analyses of a forced turbulence simulated by the lattice Boltzmann method. https://arxiv.org/abs/cond-mat/0307604

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