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

摘要

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