Experiments in Fluids

, 56:126 | Cite as

The effect of aspect ratio on the wake of the Ahmed body

  • J. VenningEmail author
  • D. Lo Jacono
  • D. Burton
  • M. Thompson
  • J. Sheridan
Research Article


This paper seeks to further elucidate the wake of the Ahmed body by investigating how the time-averaged flow structures vary with frontal aspect ratio. High-resolution particle image velocimetry results are provided for eight different width Ahmed geometries at \(\text {Re}_{\sqrt{FA}}=3\times 10^4\). It is shown that the narrower the body, the greater the downwash over the back slant, meaning the flow remains more attached. At a critical aspect ratio ( Open image in new window \(=1.9\)), the flow downstream changes. The separation over the back slant is shown to be affected by the Open image in new window , and this in turn has a significant effect on the circulation in the c-pillar vortices.


Vortex Vorticity Particle Image Velocimetry Recirculation Region Horseshoe Vortex 
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.



The authors would like to thank Mr T. McQueen and Ms R. Gardiner for their assistance with the data acquisition for this experiment. The authors would like to acknowledge the financial support of the Australian Research Council (ARC) through Linkage Project LP0991170 and the Centre National de la Recherche Scientifique (CNRS) through Grant No. PICS161793 under the Projet International de Coopération Scientifique.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • J. Venning
    • 1
    Email author
  • D. Lo Jacono
    • 1
    • 2
  • D. Burton
    • 3
  • M. Thompson
    • 1
  • J. Sheridan
    • 1
  1. 1.Fluids Laboratory for Aeronautical and Industrial Research (FLAIR), Department of Mechanical and Aerospace EngineeringMonash UniversityClaytonAustralia
  2. 2.Institut de Mécanique des Fluides de Toulouse (IMFT), CNRS, UPSUniveristé de ToulouseToulouseFrance
  3. 3.Department of Mechanical and Aerospace EngineeringMonash UniversityClaytonAustralia

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