On the relation of near-wall streamwise vortices to wall skin friction in turbulent boundary layers

Abstract
Databases from direct numerical simulations of fully developed turbulent channel flow were used to examine the relation between skin-friction on the wall and streamwise vortices observed near the wall. It is shown that the wall shear rate correlates with streamwise vortices near the wall and that the maximum correlation occurs downstream and with lateral displacement from the location of skin-friction measurement. Conditionally-averaged statistics taken near high skin-friction regions indicate that the higher skin-friction values are associated with streamwise vortices located closer to the wall. Visual studies of the time evolution of near-wall streamwise vortices and skin-friction on the wall also indicate that the high skin-friction footprints on the wall can be attributed to streamwise vortices.

This publication has 8 references indexed in Scilit: