Time-resolved volumetric particle tracking velocimetry of large-scale vortex structures from the reattachment region of a laminar separation bubble to the wake


The present paper presents time-resolved volumetric Particle Tracking Velocimetry measurements in a water towing tank on a SD7003 airfoil, performed at a Reynolds number of 60,000 and a 4° angle of attack. The SD7003 airfoil was chosen because of its long mid-chord and stable laminar separation bubble (LSB), occurring on the suction side of the airfoil at low Reynolds numbers. The present study focuses on the temporal resolution of unsteady large-scale vortex structures emitted from the LSB. In contrast to other studies, where only the observation of the flow in the transition region was examined, the entire flow from the leading edge to the far wake of the airfoil was investigated here.

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  1. Alam M, Sandham ND (2000) Direct numerical simulation of “Short” laminar separation bubbles with turbulent reattachment. J Fluid Mech 410:1–28

    Article  MATH  Google Scholar 

  2. Burgmann S, Dannemann J, Schröder W (2007) Time-resolved and volumetric PIV measurements of a transitional separation bubble on an SD7003 airfoil. Exp Fluids 44: 609–622

    Article  Google Scholar 

  3. Burgmann S, Schröder W (2008) Investigation of the vortex induced unsteadiness of a separation bubble via time-resolved and scanning PIV measurements. Exp fluids 45: 675–691

    Article  Google Scholar 

  4. Gaster M (1966) The structure and behaviour of laminar separation bubbles. AGARD CP-4, pp 813–854

  5. Hain R (2009) Untersuchung der Dynamik laminarer Ablöseblasen mit der zeitaufgelösten particle image velocimetry. Ph.D. Thesis, Technical University Braunschweig

  6. Hain R, Kähler CJ (2005) Advanced evaluation of time-resolved PIV image sequences. In: 6th International symposium on particle image velocimetry, Pasadena, 21–23 September

  7. Hain R, Kähler CJ, Radespiel R (2009) Dynamics of laminar separation bubbles at low-Reynolds number aerofoils. J Fluid Mech 630:129–153

    Article  Google Scholar 

  8. Horton H (1968) Laminar separation bubbles in two and three-dimensional incompressible flow. Ph.D. Thesis, Department of aeronautical engineering, Queen Mary College/University of London

  9. Jeong J, Hussain F (1995) On the identication of a vortex. J Fluid Mech 285:69–94

    Article  MATH  MathSciNet  Google Scholar 

  10. Ol MV, Hanff E, McAuliffe B, Scholz U, Kähler CJ (2005) Comparison of laminar separation bubble measurements on a low Reynolds number airfoil in three facilities. In: 35th AIAA fluid dynamics conference and exhibit, Toronto, 6–9 June

  11. Pauley LL, Moin P, Reynolds WC (1990) The structure of two-dimensional separation. J Fluid Mech 220:397–411

    Article  Google Scholar 

  12. Pereira F, Gharib M, Dabiri D, Modarress D (2000) Defocusing digital particle image velocimetry: a 3-component 3-dimensional DPIV measurement technique. Application to bubbly flows. Exp Fluids Suppl S78–S84

  13. Pereira F, Stuer H, Graff EC, Gharib M (2006) Two-frame 3D particle tracking. Meas Sci Technol 17:1680–1692

    Article  Google Scholar 

  14. Spalart P, Strelets M (2000) Mechanisms of transition and heat transfer in a separation bubble. J Fluid Mech 403:329–349

    Article  MATH  Google Scholar 

  15. Troolin DR, Longmire EK (2009) Volumetric velocity measurements of vortex rings from inclined exits. Exp Fluids 48:409–420

    Article  Google Scholar 

  16. Watmuff JH (1999) Evolution of a wave packet into vortex loops in a laminar separation bubble. J Fluid Mech 397:119–169

    Article  MATH  MathSciNet  Google Scholar 

  17. Willert CE, Gharib M (1992) Three-dimensional particle imaging with a single camera. Exp Fluids 12:353–358

    Article  Google Scholar 

  18. Yang Z, Voke PR (2001) Large-Eddy simulation of a boundary-layer separation and transition at a change of surface curvature. J Fluid Mech 439:305–333

    Article  MATH  Google Scholar 

  19. Zhang W, Hain R, Kähler CJ (2008) Scanning PIV investigation of the laminar separation bubble on a SD7003 airfoil. Exp Fluids 45:725–743

    Article  Google Scholar 

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The authors like to thank Prof. Münch and Mr. Banachowicz from the University of German Armed Forces Munich for providing the test facility and their technical support.

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Correspondence to E. Wolf.

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Wolf, E., Kähler, C.J., Troolin, D.R. et al. Time-resolved volumetric particle tracking velocimetry of large-scale vortex structures from the reattachment region of a laminar separation bubble to the wake. Exp Fluids 50, 977–988 (2011). https://doi.org/10.1007/s00348-010-0973-2

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  • Vortex
  • Particle Image Velocimetry
  • Vortex Structure
  • Suction Side
  • Adverse Pressure Gradient