The spanwise spectra in wall-bounded turbulence

Spatial signatures of retrograde spanwise vortices in wall turbulence

The spatial signatures of retrograde spanwise vortices in wall turbulence are assessed from particle-image velocimetry measurements in the streamwise–wall-normal plane of a zero-pressure-gradient turbulent boundary layer at Reτ ≡ u∗δ/ν=2350. The present results suggest that a proportion of retrograde spanwise vortices have a welldefined spatial relationship with neighbouring prograde vortices. ...

Wall-bounded turbulence

Coherent structures in wall-bounded turbulence.

The inherent difficulty of understanding turbulence has led to researchers attacking the topic in many different ways over the years of turbulence research. Some approaches have been more successful than others, but most only deal with part of the problem. One approach that has seen reasonable success (or at least popularity) is that of attempting to deconstruct the complex and disorganised tur...

Spatial averaging of streamwise and spanwise velocity measurements in wall-bounded turbulence using vee- and times-probes

The effect of finite dimensions of ∨and ×-probes is investigated for the measurement of mean and variances of streamwise and spanwise velocities in wall-turbulence. The probes are numerically simulated using a Direct Numerical Simulation database of channel flow at a friction Reynolds number (Reτ ) of 934 by varying the probe parameters, namely, the wire-lengths (l), the angle between the wires...

Phenomenology of wall-bounded Newtonian turbulence.

We construct a simple analytic model for wall-bounded turbulence, containing only four adjustable parameters. Two of these parameters are responsible for the viscous dissipation of the components of the Reynolds stress tensor. The other two parameters control the nonlinear relaxation of these objects. The model offers an analytic description of the profiles of the mean velocity and the correlat...