Near-wall phenomena in turbulent separated flows

  • H. H. Fernholz
Part of the Acta Mechanica book series (ACTA MECH.SUPP., volume 4)


A comparison is presented of experimental results such as pressure, skin friction (mean and higher moments), and reverse-flow factor to demonstrate the differences between weak and strong closed reverse-flow regions. The driving mechanisms are shear stress or pressure combined with shear stress, causing clearly distinctive distributions of the mean skin friction and its intensity. The “failure” of the reverse-flow parameter reaching 100% in the centre of the separation bubble can be explained by lumps of the free shear layer penetrating to the wall from above and flowing partly downstream near the wall. The outer layer flow structures interact with near-wall streaky structures moving upstream which differ considerably in width and length from those observed in boundary layers. These structures are shown by spanwise correlation measurements and by flow visualization. Suggestions are made for model flows covering weak and strong reverse-flow regions, respectively.


Shear Layer Skin Friction Turbulent Boundary Layer Reynolds Shear Stress Separate Shear Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • H. H. Fernholz
    • 1
  1. 1.Hermann-Föttinger-Institut für Thermo- und FluiddynamikTechnische Universität BerlinBerlinFederal Republic of Germany

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