Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
Skip to main content
Springer Nature Link
Log in

Scanning PIV investigation of the laminar separation bubble on a SD7003 airfoil

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

Abstract

A laminar separation bubble occurs on the suction side of the SD7003 airfoil at an angle of attack α =  4–8° and a low Reynolds number less than 100,000, which brings about a significant adverse aerodynamic effect. The spatial and temporal structure of the laminar separation bubble was studied using the scanning PIV method at α =  4° and Re = 60,000 and 20,000. Of particular interest are the dynamic vortex behavior in transition process and the subsequent vortex evolution in the turbulent boundary layer. The flow was continuously sampled in a stack of parallel illuminated planes from two orthogonal views with a frequency of hundreds Hz, and PIV cross-correlation was performed to obtain the 2D velocity field in each plane. Results of both the single-sliced and the volumetric presentations of the laminar separation bubble reveal vortex shedding in transition near the reattachment region at Re = 60,000. In a relatively long distance vortices characterized by paired wall-normal vorticity packets retain their identities in the reattached turbulent boundary layer, though vortices interact through tearing, stretching and tilting. Compared with the restricted LSB at Re = 60,000, the flow at Re = 20,000 presents an earlier separation and a significantly increased reversed flow region followed by “huge” vortical structures.

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

Access this article

Log in via an institution

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

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

Similar content being viewed by others

References

  1. Adrian RJ, Christensen KT, Liu XF (2000) Analysis and interpretation of instantaneous turbulent velocity fields. Exp Fluids 29:275–290

    Article  Google Scholar 

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

    Google Scholar 

  3. Brücker Ch, Althaus W (1992) Study of vortex breakdown by particle tracking velocimetry (PTV) Part I: bubble-type vortex breakdown. Exp Fluids 13:339–349

    Article  Google Scholar 

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

    Article  Google Scholar 

  5. Brücker Ch (1997a) 3D scanning PIV applied to an air flow in a motored engine using digital high-speed video. Meas Sci Technol 8:1480–1492

    Article  Google Scholar 

  6. Brücker Ch (1997b) Study of the three-dimensional flow in a T-junction using a dual-scanning method for three-dimensional scanning-particle-image velocimetry (3-D SPIV). Exp Thermal Fluid Sci 14:35–44

    Article  Google Scholar 

  7. Brücker Ch, Burgmann S, Schröder W (2005) Scanning PIV measurements of a laminar separation bubble. 2006. In: 6th international symposium on particle image velocimetry. Pasadena, 21–23 Sep, 2005

  8. Burgmann S, Schröder W, Brücker Ch (2006a) Volumetric measurement of vortical structures in the reattachment region of a laminar separation bubble using stereo scanning PIV. In: 13th international symposium on applied laser techniques to fluid mechanics

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

    Article  Google Scholar 

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

  11. Eisenbach S, Friedrich R (2008) Large-eddy simulation of flow separation on an airfoil at a high angle of attack and Re = 100,000 using Cartesian grids. Theor Comput Fluid Dyn 22:213–225

    Google Scholar 

  12. Elsinga GE, Oudheusden BW, van Scarano F (2005) The effect of particle image blur on the correlation map and velocity measurement in PIV. In: Proceedings of the optical engineering and instrumentation, SPIE annual meeting, paper 5880-37. San Diego

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

  14. Hain R, Kähler CJ, Michaelis D (2007) Tomographic and time resolved PIV measurements on a finite cylinder mounted on a flat plate. In: 7th international symposium on particle image velocimetry, Roma, 11–14 Sep

  15. Häggmark CP, Bakchinov AA, Alfredsson PH (2000) Experiments on a two-dimensional laminar separation bubble. Philos Trans R Soc Lond A 358:3193–3205

    Article  MATH  Google Scholar 

  16. Hori T, Sakakibara J (2004) High-speed scanning stereoscopic PIV for 3D vorticity measurement in liquids. Meas Sci Technol 15:1067–1078

    Article  Google Scholar 

  17. Horton (1968) Laminar separation bubbles in two- and three-dimensional incompressible flow. Ph.D thesis, University of London

  18. Hu H, Yang Z (2008) An experimental study of the laminar flow separation on a low-reynolds-number airfoil. J Fluids Eng 130:051101

    Article  Google Scholar 

  19. Jones LE, Stanberg RD, Sandham ND (2008) Direct numerical simulations of forced and unforced separation bubbles on an airfoil at incidence. J Fluid Mech 602:175–207

    Article  MATH  Google Scholar 

  20. Kähler CJ (2004) Investigation of the spatio-temporal flow structure in the buffer region of a turbulent boundary layer by means of multiplane stereo PIV. Exp. Fluids 36:114–130

    Article  Google Scholar 

  21. Kähler CJ (2004) The significance of turbulent eddies for the mixing in boundary layers. In: Meier, Sreenivasan, Heinemann (eds) IUTAM symposium on "one hundred years of boundary layer research", Solid mechanics and its application, Göttingen, 11–14 Aug 2006, vol 129, Springer, Heidelberg

  22. Kelso RM, Delo C (2000) Three-dimensional Imaging. In: Smits AJ, Lim TT (eds) Flow visualization: techniques and examples, vol 10, Imperial College Press, 245–288

  23. Lang M, Rist U, Wagner S (2004) Investigations on controlled transition development in a laminar separation bubble by means of LDA and PIV. Exp Fluids 36:43–52

    Article  Google Scholar 

  24. 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: AIAA paper 2005–5149, 35th AIAA fluid dynamics conference and exhibit, Toronto, 6–9 June

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

    Article  Google Scholar 

  26. Radespiel R, Windte J, Scholz U (2007) Numerical and experimental flow analysis of moving airfoils with laminar separation bubbles. AIAA J 45(6):1346–1356

    Article  Google Scholar 

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

  28. Rist U (2003) Instability and transition mechanisms in laminar separation bubbles, RTO-AVT-VKI lecture series 2004, 24–28 Nov, 2003

  29. Spalart PR, Strelets MK (2000) Mechanism of transition and heat transfer in a separation bubble. J Fluid Mech 403:329–349

    Article  MATH  Google Scholar 

  30. 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 

  31. Windte J, Radespiel R, Scholz U, Eisfeld B (2004) RANS simulation of the transitional flow around airfoils at low Reynolds Numbers for steady and unsteady onset conditions. ADA442472

  32. Yang Z, Voke PR (2001) Large-eddy simulation of boundary-layer separation and transition at a change of surface curvature. J Fluid Mech 493:305–333

    Google Scholar 

  33. Yuan W, Khalid MC, Windte J, Scholz U, Radespiel R (2005) An investigation of Low-Reynolds-Number flows past airfoils. In: AIAA-2005-4607, 23rd AIAA applied aerodynamics conference, Toronto, 6–9 June

Download references

Acknowledgments

This research has been supported by the German Research Foundation (DFG) in the priority program 1147 "Bildgebende Messverfahren für die Strömungsanalyse".

Author information

Author notes

  1. Wei Zhang

    Present address: Department of Aerospace Engineering, Iowa State University, Ames, IA, 50014, USA

  2. Rainer Hain

    Present address: Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Institut für Aerodynamik und Strömungstechnik, Lilienthalplatz 7, 38108, Braunschweig, Germany

  3. Christian J. Kähler

    Present address: Institut für Strömungsmechanik und Aerodynamik, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany

Authors and Affiliations

  1. Institut für Strömungsmechanik, Technische Universität Braunschweig, Bienroder Weg 3, 38106, Braunschweig, Germany

    Wei Zhang, Rainer Hain & Christian J. Kähler

Authors
  1. Wei Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Rainer Hain
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Christian J. Kähler
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Christian J. Kähler.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Zhang, W., Hain, R. & Kähler, C.J. Scanning PIV investigation of the laminar separation bubble on a SD7003 airfoil. Exp Fluids 45, 725–743 (2008). https://doi.org/10.1007/s00348-008-0563-8

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00348-008-0563-8

Keywords

Search

Navigation