Skip to main content
Log in

A two-element high-lift airfoil in disturbed flow conditions

  • Original Paper
  • Published:
CEAS Aeronautical Journal Aims and scope Submit manuscript

Abstract

This contribution presents experimental results of a two-element high-lift airfoil in a disturbed inflow. Permanent disturbances are generated by the wakes of two static airfoils located upstream of the research airfoil, one of which is a planar wake by an infinite airfoil and the other is a longitudinal vortex emanating from a finite wing. The disturbances induce spanwise gradients into the flow. The disturbed flow field is measured by Particle Image Velocimetry. The interaction of the disturbed flow field with the high-lift airfoil is investigated by means of static surface pressure close to the airfoil’s leading- and trailing-edge, as well as surface hotfilm measurements and oil flow visualizations on the high-lift flap. For small and moderate incidences the airfoil is mainly influenced by the circulation induced by the disturbances, which affect the effective flow angles. Local effects that result from the turbulence in the airfoil-wake and the induced transverse velocity of the disturbances are likewise considered. At high angle of attack, the prevailing stall conditions with strong variations in spanwise direction are discussed.

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

Access this article

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

Instant access to the full article PDF.

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

Similar content being viewed by others

References

  1. Hahn, D., Scholz, P., Semaan, R., Radespiel, R., Müller-Eigner, R.: Erzeugung definierter Querwirbel in einer geschlossenen Messstrecke,’ 60. Deutscher Luft- und Raumfahrtkongress, DGLR, Bremen (2011)

  2. Klein, S., Hoppmann, D., Scholz, P., Radespiel, R.: High-lift airfoil interacting with a vortical disturbance: wind-tunnel measurements. AIAA J. 53(6), 1681–1692 (2015)

    Article  Google Scholar 

  3. Klein, S., Scholz, P., Radespiel, R.: Interaction of three-dimensional disturbances with the flow around a two-element high-lift airfoil, 4th Symposium “Simulation of Wing and Nacelle Stall”. TU Braunschweig, Braunschweig (2014)

    Google Scholar 

  4. Ham, N.D.: Some conclusions from an investigation of blade–vortex interaction. J. Am. Helicopter Soc. 20, 26–31 (1975)

    Article  Google Scholar 

  5. Patel, M.H., Hancock, G.J.: Some experimental results of the effect of a streamwise vortex on a two-dimensional wing. Aeronaut. J. 78(760), 151–155 (1974)

    Google Scholar 

  6. Bodstein, G.C.R., George, A.R., Hui, C.Y.: The three-dimensional interaction of a streamwise vortex with a large-chord lifting surface: theory and experiment. J. Fluid Mech. 322, 51–79 (1996)

    Article  MATH  Google Scholar 

  7. McAlister, K.W., Tung, C.: Interaction between an airfoil and a streamwise vortex, 17th Fluid Dynamics, Plasma Dynamics, and Lasers Conference, AIAA-84-1626, Snowmass (1984)

  8. Rockwell, D.: Vortex–body interaction. Annu. Rev. Fluid Mech. 30, 199–229 (1998)

    Article  MathSciNet  Google Scholar 

  9. Beck, N., Radespiel, R., Lenfers, C., Friedrichs, J., Rezaeian, A.: Aerodynamic effects of propeller slipstream on a wing with circulation control. J. Aircr. 52(5), 1422–1436 (2015)

    Article  Google Scholar 

  10. Haines, A.B., Young, A.D.: Scale effects on aircraft and weapon aerodynamic. AGARDograph 323, 27–65 (1994)

    Google Scholar 

  11. Landa, T., Radespiel, R., Wild, J.: Numerical simulations of streamwise vortices on a generic high-lift configuration, 54th AIAA Aerospace Sciences Meeting, AIAA-2016-0304, San Diego (2016)

  12. Helmke, C., Auerswald, T., Raasch, S., Bange, J.: Comparison of two methods to provide highly resolved atmospheric turbulence data for simulations of wing and nacelle circulations, 2nd Symposium “Simulation of Wing and Nacelle Stall’’. TU Braunschweig, Braunschweig (2010)

    Google Scholar 

  13. Wild, J.: Mach and Reynolds number dependencies of the stall behavior of high-lift wing-sections. J. Aircr. 50(4), 1202–1216 (2013)

    Article  Google Scholar 

  14. Scholz, P., Kähler, C.J., Radespiel, R., Wild, J., Wichmann, G.: Active control of leading-edge separation within the German Flow Control Network, 47th AIAA Aerospace Science Meeting, AIAA-2009-529, Orlando (2009)

  15. Hahn, D., Scholz, P., Radespiel, R.: Experimental evaluation of the stall characteristics of a two-element high lift airfoil, 2nd Symposium “Simulation of Wing and Nacelle Stall’’, SFB FOR 1066, Braunschweig (2010)

  16. Simpson, R.L.: Turbulent boundary-layer separation. Annu. Rev. Fluid Mech. 21, 205–234 (1989)

    Article  MATH  Google Scholar 

  17. Wawrzinek, K.P., Lutz, T., Krämer, E.: Numerical studies of turbulent flow influence on a two-element airfoil, 4th Symposium “Simulation of Wing and Nacelle Stall”. TU Braunschweig, Braunschweig (2014)

    Google Scholar 

  18. Reuß, S., Probst, A., Knopp, T., Wawrzinek, K.P.: Hybrid RANS/LES study of the development of an airfoil-generated vortex, 4th Symposium “Simulation of Wing and Nacelle Stall”. TU Braunschweig, Braunschweig (2014)

    Google Scholar 

  19. Radespiel, R., et al.: Simulation of wing and nacelle stall, 54th AIAA Aerospace Sciences Meeting, AIAA. 2016-1830, San Diego (2016)

Download references

Acknowledgements

The members of the FOR 1066 research group gratefully acknowledge the support of the “Deutsche Forschungsgemeinschaft DFG” (German Research Foundation) which funded this research.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to S. Klein.

Additional information

This paper is based on a presentation at the German Aerospace Congress, September 22–24, 2015, Rostock, Germany.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Klein, S., Scholz, P. & Radespiel, R. A two-element high-lift airfoil in disturbed flow conditions. CEAS Aeronaut J 8, 79–91 (2017). https://doi.org/10.1007/s13272-016-0221-4

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s13272-016-0221-4

Keywords

Navigation