Passive scalars in turbulent channel flow at high Reynolds number

Transport of Passive Scalars in Turbulent Channel Flow

A direct numerical simulation of a turbulent channel flow with three passive scalars at different molecular Prandtl numbers is performed. Computed statistics including the turbulent Prandtl numbers are compared with existing experimental data. The computed fields are also examined to investigate the spatial structure of the scalar fields. The scalar fields are highly correlated with the streamw...

Surface-sampled simulations of turbulent flow at high Reynolds number

Funding information European Commission Horizon 2020, Grant/Award Number: 671571; Engineering and Physical Sciences Research Council (EPSRC), Grant/Award Number: EP/L000261/1 Summary A new approach to turbulence simulation, based on a combination of large eddy simulation (LES) for the whole flow and an array of non–space-filling quasi-direct numerical simulations (QDNS), which sample the respon...

DNS and LES of Scalar Transport in a Turbulent Plane Channel Flow at Low Reynolds Number

The paper reports on DNS and LES of plane channel flow at Reτ = 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,...

Interactions within the turbulent boundary layer at high Reynolds number

Simultaneous streamwise velocity measurements across the vertical direction obtained in the atmospheric surface layer (Reτ 5 × 10) under near thermally neutral conditions are used to outline and quantify interactions between the scales of turbulence, from the very-large-scale motions to the dissipative scales. Results from conditioned spectra, joint probability density functions and conditional...

On filtering in the viscous-convective subrange for turbulent mixing of high Schmidt number passive scalars