Influences of boundary layer scale separation on the vorticity transport contribution to turbulent inertia

Abstract

In the flows of interest, the mean effect of turbulent inertia can be expressed as the difference of two velocity vorticity correlations. This difference must be sufficiently non-zero if turbulent inertia is to have a net influence on the mean dynamics. One of the correlations is physically related to change of scale effects, while the other is related to advective vorticity transport. The vorticity transport mechanism is studied under the influence of increasing scale separation. Through the use of both laboratory and field data, the scale separation between the fluctuations of wall-normal velocity, v, and spanwise vorticity ωz, are shown to increase with distance from the wall and Reynolds..