Streamwise Vortices Generated by Rolling Up Shear Layers

Christoph Strangfeld
Karsten Düwel
Christian N. Nayeri
Christian O. Paschereit
Technische Universität Berlin

Image by C. Strangfeld and K. Düwel/TU-Berlin

Streamwise vortices produce strong low pressure regions and are generated on delta-wings, on the leeward side of trains, and at slanted rear ends of road vehicles and helicopters. In the presented experimental flow visualization (smoke in air), the flow separates downstream of a generic model: a swept, semi-span backward facing step. The separated flow rolls up into the vortex along the entire edge. The shear layer between the vortex core and the free stream is subjected to Kelvin-Helmholtz instabilities and continuously produces vorticity. Finally downstream, the shear layer vorticity convects into the vortex core and increases its circulation.

Usage Information

This image may be freely reproduced with the accompanying credit: C. Strangfeld and K. Düwel/ TU-Berlin

Contact Information

Christoph Strangfeld
Institute of Fluid Dynamics and Technical Acoustics
-Hermann-Föttinger Institut-
Chair of Fluid Dynamics
Technische Universität Berlin

Technische Universität Berlin
Gebäude HF
Müller-Breslau-Str. 8
10623 Germany
Strangfeld@tu-berlin.de