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Experiments in Fluids

, Volume 45, Issue 4, pp 715–724 | Cite as

Tomographic and time resolved PIV measurements on a finite cylinder mounted on a flat plate

  • Rainer Hain
  • Christian J. KählerEmail author
  • Dirk Michaelis
Research Article

Abstract

Tomographic and time resolved PIV measurements were performed to examine the 3D flow topology and the flow dynamic above the upper surface of a low-aspect ratio cylinder at Re ≈ 1 ×  105. This generic experiment is of fundamental interest because it represents flow features which are relevant to many applications such as laminar separation bubbles and turbulent reattachment. At Re  ≈ 1 × 105, laminar separation bubbles arise on the side of the cylinder. Furthermore, on the top of the cylinder a separation with reattachment is of major interest. The tomographic PIV measurement, which allows to determine all three velocity components in a volume instantaneously, was applied to examine the flow topology and interaction between the boundary layer and wake structures on the top of the finite cylinder. In the instantaneous flow fields the tip vortices and the recirculation region becomes visible. However, it is also observed that the flow is quite unsteady due to the large separation occurring on the top of the cylinder. In order to study the temporal behaviour of the separation, time resolved PIV was applied. This technique allows capturing the dynamic processes in detail. The development of vortices in the separated shear layer is observed and in addition regions with different dominant frequencies are identified.

Keywords

Vortex Shear Layer Strouhal Number Laminar Separation Bubble Instantaneous Flow Field 
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.

Notes

Acknowledgments

The authors acknowledge the support by PCO for providing two PCO pco.4000 cameras for the tomographic PIV measurements. This research has been supported by the German Research Foundation (DFG) in the priority program 1147 "Bildgebende Messverfahren für die Strömungsanalyse".

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Rainer Hain
    • 1
    • 2
  • Christian J. Kähler
    • 1
    • 3
    Email author
  • Dirk Michaelis
    • 4
  1. 1.Institut für StrömungsmechanikTechnische Universität BraunschweigBrunswickGermany
  2. 2.Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Institut für Aerodynamik und StrömungstechnikBrunswickGermany
  3. 3.Institut für Strömungsmechanik und Aerodynamik LRT-7Universität der Bundeswehr MünchenNeubibergGermany
  4. 4.LaVision GmbHGöttingenGermany

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