General Points - Transport and Coherent Structures in Wall Turbulence - page 52

created by the stretching of the spanwise vorticity in
immediate proximity. It is then tilted, again because of the
mean shear, to create the streamwise component , which

can “roll up” and develop into QSVs that play a fundamental
role in the structure of the wall turbulence, and constitutes
the main subject of this topic. This suggestion is represented
in Figure 1.20.

ω

x

Figure 1.21. Turbulent intensities of the spanwise, wall-normal and
streamwise vorticity components in a fully developed turbulent channel
flow for 180 , respectively, according to Bauer [BAU 14]. The

turbulent intensities of the spanwise and streamwise components increase
with the Reynolds number, whereas the intensity of the wall-normal
component is remarkably immune to variations in Re

<<

Re 1,100

. Also see [GIR 06]

τ

1.11.2. Turbulent intensities of the fluctuating vorticity
components

Figure 1.21 shows the distribution of turbulent intensities
of the vorticity components in the range 180

arising from our own direct numerical simulations [BAU 14]
and corresponding closely to the results found by [HOY 08].
The intensities of the streamwise and spanwise components
increase in line with the Reynolds number, particularly in
the buffer sublayer. However, the intensity

Re << 1,100

+

remains

σ

ω

y