DNS and LES of scalar transport in a turbulent plane channel flow at low Reynolds number

Abstract

The paper reports on DNS and LES of plane channel flow at Re τ = 180 and compares these to a DNS with a higher order convection scheme. For LES different subgrid-scale models like the Smagorinsky, the Dynamic Smagorinsky and the Dynamic Mixed Model were used with the grid being locally refined in the near-wall region. The mixing of a passive scalar has been simulated with two convection schemes, central differencing and HLPA. The latter exhibits numerical diffusion and the results with the central scheme are clearly superior. LES with this scheme reproduced the budget of the scalar variance equation reasonably well. © 2008 Springer.