Skip to main content
SpringerLink
Log in

Time-resolved and volumetric PIV measurements of a transitional separation bubble on an SD7003 airfoil

  • Research Article
  • Published:
Experiments in Fluids Aims and scope Submit manuscript

Abstract

To comprehensively understand the effects of Kelvin–Helmholtz instabilities on a transitional separation bubble on the suction side of an airfoil regarding as to flapping of the bubble and its impact on the airfoil performance, the temporal and spatial structure of the vortices occurring at the downstream end of the separation bubble is investigated. Since the bubble variation leads to a change of the pressure distribution, the investigation of the instantaneous velocity field is essential to understand the details of the overall airfoil performance. This vortex formation in the reattachment region on the upper surface of an SD7003 airfoil is analyzed in detail at different angles of attack. At a Reynolds number Re c < 100,000 the laminar boundary layer separates at angles of attack >4°. Due to transition processes, turbulent reattachment of the separated shear layer occurs enclosing a locally confined recirculation region. To identify the location of the separation bubble and to describe the dynamics of the reattachment, a time-resolved PIV measurement in a single light-sheet is performed. To elucidate the spatial structure of the flow patterns in the reattachment region in time and space, a stereo scanning PIV set-up is applied. The flow field is recorded in at least ten successive light-sheet planes with two high-speed cameras enclosing a viewing angle of 65° to detect all three velocity components within a light-sheet leading to a time-resolved volumetric measurement due to a high scanning speed. The measurements evidence the development of quasi-periodic vortex structures. The temporal dynamics of the vortex roll-up, initialized by the Kelvin–Helmholtz (KH) instability, is shown as well as the spatial development of the vortex roll-up process. Based on these measurements a model for the evolving vortex structure consisting of the formation of c-shape vortices and their transformation into screwdriver vortices is introduced.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20 
Fig. 21
Fig. 22

Similar content being viewed by others

References

  • Brücker Ch (1995) Digital-particle-image-velocimetry (DPIV) in a scanning light-sheet: 3D starting flow around a short cylinder. Exp Fluids 19(4):255–263

    Article  Google Scholar 

  • Brücker Ch, Althaus W (1992) Study of vortex breakdown by particle tracking velocimetry (PTV). Exp Fluids 13(5):339–349

    Article  Google Scholar 

  • Burgmann S, Schröder W, Brücker Ch (2006a) Scanning PIV measurements of a laminar separation bubble. Exp Fluids 41(2):319–326

    Google Scholar 

  • Burgmann S, Schröder W, Brücker Ch (2006b) Volumetric measurement of vortical structures in the reattachment region of a laminar separation bubble using stereo scanning PIV. 13th International symposium on particle image velocimetry, Lisbon, June 26–29

  • Fitzgerald EJ, Mueller TJ (1990) Measurements in a separation bubble on an airfoil using laser velocimetry. AIAA J 28(4):584–592

    Google Scholar 

  • Gad-el-Hak M (2001) Micro-air-vehicles: can they be controlled better? J Aircr 38(3):419–429

    Google Scholar 

  • Gaster M (1966) The structure and behaviour of laminar separation bubbles. AGARD CP-4, Flow sep, Part 2:813–854

    Google Scholar 

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

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

    Article  MATH  MathSciNet  Google Scholar 

  • Keane RD, Adrian RJ (1990) Optimization of particle image velocimeters, part 1: double pulsed systems. Meas Sci Technol 1:1202–1215

    Article  Google Scholar 

  • Lang M, Rist U, Wagner S (2004) Investigations on disturbance amplification in a laminar separation bubble by means of LDA and PIV. Exp Fluids 36(1):43–52

    Article  Google Scholar 

  • Malkiel M, Mayle RE (1996) Transition in a separation bubble. J Turbomach 118:752–759

    Article  Google Scholar 

  • Maucher U, Rist U, Wagner S (1994) Direct numerical simulations of airfoil separation bubbles, computational fluid dynamics. 2nd ECCOMAS conference, September 5–8, 1994, Stuttgart. Wiley, pp 471–477

  • McAuliffe BR, Yaras MI (2005) Separation-bubble-transition measurements on a low-Re airfoil using particle image velocimetry. Proceedings of GT2005, ASME Turbo Expo 2005, Reno, June 6–9, GT2005–68663

  • Nash JF, Scruggs RM (1977) Unsteady boundary layer with reversal and separation, AGARD conference on unsteady aerodynamics, AGARD-CP-227

  • Ol MV, Hanff E, McAuliffe B, Scholz U, Kaehler C (2005) Comparison of laminar separation bubble measurements on a low Reynolds number airfoil in three facilities. AIAA paper 2005–5149, 35th AIAA fluid dynamics conference and exhibit, Toronto, June 6–9

  • O’Meara MM, Mueller TJ (1987) Laminar separation bubble characteristics on an airfoil at low Reynolds numbers. AIAA J 25(8):1033–1041

    Google Scholar 

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

    Article  Google Scholar 

  • Prasad AK, Jensen K (1995) Scheimpflug stereocamera for particle image velocimetry in liquid flows. Appl Opt 34(30):7092–7099

    Article  Google Scholar 

  • Rist U (2002) On instabilities and transition in laminar separation bubbles. Proc CEAS aerospace aerodynamics research conference, 10–12 June, Cambridge

  • Roberts WB (1980) Calculation of laminar separation bubbles and their effect on airfoil performance. AIAA J 18(1):25–31

    Article  Google Scholar 

  • Selig MS, Guglielmo JJ, Broeren AP, Giguère P (1995) Summary of low-speed airfoil data 1. SoarTech, Virginia Beach. 292 p

    Google Scholar 

  • Tsai RY (1986) An efficient and accurate camera calibration technique for 3D machine vision, proceedings of IEEE conference on computer vision and pattern recognition. Miami Beach, 1986:364–374

    Google Scholar 

  • Volino RJ, Hultgren LS (2001) Measurements in separated and transitional boundary layers under low-pressure turbine airfoil conditions. J Turbomac 123:189–197

    Article  Google Scholar 

  • Watmuff JH (1999) Evolution of a wave packet into vortex loops in a laminar separation bubble. J Fluid Mech 397:119–170

    Article  MATH  MathSciNet  Google Scholar 

  • Wieneke B (2005) Stereo-PIV using self-calibration on particle images. Exp Fluids 39(2):267–280

    Article  Google Scholar 

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

    Article  MATH  Google Scholar 

  • Yuan W, Khalid M, Windte J, Scholz U, Radespiel R (2005) An Investigation of low-Reynolds-number flows past airfoils. 23rd AIAA applied aerodynamics conference, Toronto, June 6–9

Download references

Acknowledgments

This work was funded by the Deutsche Forschungsgemeinschaft in the priority research program “SPP 1147 Bildgebende Messverfahren für die Strömungsanalyse” (experimental visualization methods for flow analysis) under the contract SCHR 309/25.

Author information

Authors and Affiliations

  1. Department of Mechanical Engineering, Institute of Aerodynamics, RWTH Aachen University, Wüllnerstrasse 5a, 52062, Aachen, Germany

    S. Burgmann, J. Dannemann & W. Schröder

Authors
  1. S. Burgmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. J. Dannemann
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. W. Schröder
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to S. Burgmann.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Burgmann, S., Dannemann, J. & Schröder, W. Time-resolved and volumetric PIV measurements of a transitional separation bubble on an SD7003 airfoil. Exp Fluids 44, 609–622 (2008). https://doi.org/10.1007/s00348-007-0421-0

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00348-007-0421-0

Keywords

Search

Navigation