Lagrangian Structure Functions in Turbulence: Scaling Exponents and Universality

Victor Yakhot

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arXiv · 0810.2955

Lagrangian Structure Functions in Turbulence: Scaling Exponents and Universality

Victor Yakhot

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Abstract

In this paper, the approach for investigation of asymptotic ($Re\to \infty$) scaling exponents of Eulerian structure functions (J. Schumacher et al, New. J. of Physics {\bf 9}, 89 (2007)) is generalized to studies of Lagrangian structure functions in turbulence. The novel "bridging relation" based on the derived expression for the fluctuating, moment-order - dependent dissipation time $τ_{η,n}$ enabled us to calculate scaling exponents ($κ_{n}$) of the moments of Lagrangian velocity differences $S_{n,L}(τ)=\bar{(u(t+τ)-u(t))^{n}}\propto τ^{κ_{n}}$ in a good agreement with experimental and numerical data.

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Victor Yakhot. 2009-11-25. Lagrangian Structure Functions in Turbulence: Scaling Exponents and Universality. https://arxiv.org/abs/0810.2955

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