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arXiv · 1602.05022

The dissipation tensor $\varepsilon_{ij}$ in wall turbulence

G. A. Gerolymos·I. Vallet
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Abstract

The paper investigates the dissipation tensor $\varepsilon_{ij}$ in wall turbulence. Available DNS data are examined to illustrate the differences in the anisotropy of the dissipation tensor $\varepsilon_{ij}$ with respect to the anisotropy of the Reynolds-stresses $r_{ij}$. The budgets of the transport equations of the dissipation tensor $\varepsilon_{ij}$ are studied using novel DNS data of low-Reynolds-number turbulent plane channel flow with spatial resolution sufficiently fine to accurately determine the correlations of products of 2-derivatives of fluctuating velocities $u_i'$ and pressure $p'$ which appear in various terms. Finally, the influence of the Reynolds number on the diagonal components of $\varepsilon_{ij}$ ($\varepsilon_{xx}$, $\varepsilon_{yy}$, $\varepsilon_{zz}$) and on the various terms in their transport equations is studied using available DNS data of Vreman and Kuerten (Phys. Fluids 26 (2014) 085103).

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G. A. Gerolymos, I. Vallet. 2016-02-16. The dissipation tensor $\varepsilon_{ij}$ in wall turbulence. https://doi.org/10.1017/jfm.2016.610

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