Local dissipation scales and energy dissipation-rate moments in channel flow

Abstract

Local dissipation-scale distributions and high-order statistics of the energy dissipation rate are examined in turbulent channel flow using very high-resolution direct numerical simulations at Reynolds numbers Reτ = 180, 381 and 590. For sufficiently large Reτ , the dissipation-scale distributions and energy dissipation moments in the channel bulk flow agree with those in homogeneous isotropic turbulence, including only a weak Reynolds-number dependence of both the finest and largest scales. Systematic, but Reτ -independent, variations in the distributions and moments arise as the wall is approached for y+ 100. In the range 100 textless y+ textless 200, there are substantial differences in the moments between the lowest and the two larger values of Reτ . This is most likely caused by coherent vortices from the near-wall region, which fill the whole channel for low Reτ .

Publication
Journal of Fluid Mechanics
Peter Hamlington
Peter Hamlington
Associate Professor

Peter is an associate professor in the Paul M. Rady Department of Mechanical Engineering at the University of Colorado Boulder and the principal investigator of the Turbulence and Energy Systems Laboratory.