GALCIT Colloquium

The study of wall-bounded turbulent flows has received great attention over the past few years as a result of high Reynolds number experiments conducted in new high Reynolds number facilities such as the Princeton superpipe , the NDF facility in Chicago and the Melbourne wind tunnel. These experiments have brought into question the fundamental scaling laws of the turbulence and mean flow quantities as well as revealed high Reynolds number phenomena, which make extrapolation of low Reynolds number results highly questionable.

In this talk these issues will be reviewed and new results from the Melbourne wind tunnel and atmospheric surface layer on the salt-flats of Utah will be presented documenting unique high Reynolds number phenomena. Discussion will also be given to the key coherent structures in the logarithmic region and how they interact across the boundary layer. These findings lead to a new consideration of so-called inner-outer interactions and form the basis of new predictive model for the near-wall inner region, and the wall-shear stress. The implications of this will be discussed.