Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-28T06:18:26.086Z Has data issue: false hasContentIssue false
  • English
  • Français

Aerofoil flow separation suppression using dimples

Published online by Cambridge University Press:  27 January 2016

C. C. Beves  and
T. J. Barber
T. J. Barber
Affiliation:
School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, Australia
Get access Rights & Permissions [Opens in a new window]

Abstract

Flow separation is a source of aerodynamic inefficiency, by using vortex generators flow separation can be controlled. This is of particular benefit to flows around bodies which are susceptible to separated flows, such as bodies in ground effect. Previous studies on the ability of dimples to produce vortices for flow mixing concerned heat transfer applications. Experimental measurements using Laser Doppler Anemometry (LDA) were taken in the wake of the Tyrrell026 aerofoil (Rec = 0·5 × 105) with a dimple array machined in the surface. Results for a dimple array of three rows placed forward of x/c = 0·23 with 1·5D dimple to dimple spacing, showed significant flow recovery in the wake. The velocity deficit of u/Uo,min = −0·1 recovered to u/Uo,min = 0·3 with the dimple array and the size of the wake reduced by 50%; at α = 10°, h/c = 0·313. The positive effect of the dimple array on the wing reduced as the wing was brought closer to the ground.

Type
Research Article
Information
The Aeronautical Journal , Volume 115 , Issue 1168 , June 2011 , pp. 335 - 344
Copyright
Copyright © Royal Aeronautical Society 2011 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Ligrani, P.M. Flow visualization and flow tracking as applied to turbine components in gas turbine engines, Meas Sci Tech, 2000, 11, pp 992–1006.Google Scholar
2. Isaev, S.A. and Leont’Ev, A.I. Analysis of the effect of viscosity on the vortex dynamics at laminar separated flow past a dimple on a plane with allowance for its asymmetry, J Engineering Physics and Thermophysics, 2001, 74, (2), pp 339–346.Google Scholar
3. Bunker, R.S. and Donnellan, K.F. Heat transfer and friction factors for flows inside circular tubes with concavity surfaces, Proc. ASME Turbo Expo, 16-19 June 2003, Atlanta, Georgia, US.Google Scholar
4. Khalatov, A.A. and Byerley, A. Flow characteristics within and downstream of spherical and cylindrical dimple configurations on a flat plate under laminar flow conditions, Proc. of the ASME Turbo Expo, Vienna, Austria, 14-17 June 2004, ASME Paper No. GT2004-53656.Google Scholar
5. Ligrani, P.M. and Park, J. Numerical predictions of heat transfer and fluid flow characteristics for seven different dimpled surfaces in a channel, Num Heat Transfer (Part A), 2005, 47, pp 209–232.Google Scholar
6. Razenbach, R. and Barlow, J.B. Two-dimensional aerofoil in ground effect, an experimental and computational study, SAE, 1994, SAE 942509.Google Scholar
7. Razenbach, R. and Barlow, J.B. Cambered aerofoil in ground effect, an experimental and computational study, SAE, 1996, 960909.Google Scholar
8. Razenbach, R. and Barlow, J.B. Multi-element aerofoil in ground effect- an experimental and computational study, AIAA, 1997, AIAA-97-2238.Google Scholar
9. Zhang, X. and Zerihan, J. Off-surface aerodynamics measurements of a wing in ground effect, J Aircr, 2003, 40, (4), pp 716–725.Google Scholar
10. Moryossef, Y. and Levy, Y. Effect of oscillations on aerofoils in close proximity to the ground, AIAA J, 2004, 42, (9), pp 1755–1764.Google Scholar
11. Mahon, S. and Zhang, X. Computational analysis of pressure and wake characteristics on an aerofoil in ground effect, ASME, 2005, 127, pp 290–298.Google Scholar
12. Zerihan, J. An Investigation into the Aerodynamics of Wings in Ground Effect, PhD Thesis, University of Southampton, School of Engineering, 2001.Google Scholar
13. Nickerson, J.D. A study of vortex generators at low Reynolds numbers, AIAA, 1986, AIAA-86-0155.Google Scholar
14. Lin, J.C. and Howard, F.G. Investigation of several passive and active methods for turbulent flow separation control, 21st AIAA Fluid Dynamics, Plasma Dynamics and Lasers Conference, 1990, p 21.Google Scholar
15. Lin, J.C. and Robinson, S.K. Separation control on high Reynolds number multi-element aerofoils, 10th Applied Aerodynamics conference, 1992, AIAA-1992-2636.Google Scholar
16. Storms, B.L. Lift enhancement of an aerofoil using a gurney flap and vortex generators, J Aircr, 1994, 31, (3), pp 542–547.Google Scholar
17. Storms, B.L. and Ross, J.C. Experimental study of lift enhancing tabs on a two-element aerofoil, J Aircr, 1995, 32, (5), pp 1072–1078.Google Scholar
18. Klausmeyer, S.M. A flow physics study of vortex generators on a multi-element aerofoil, 34th aerospace sciences meeting and exhibit, 1996, AIAA-1996-548.Google Scholar
19. Isaev, S.A. and Sudakov, A.G. Effect of supercirculation in a flow around a thick aerofoil with vortex cells, Doklady Physics, 2001, 46, (3), pp 199–201.Google Scholar
20. Rae, A.J., Galpin, S.A. and Fulker, J. Investigation into the scale effect on the performance of sub boundary-layer on civil aircraft highlift devices, 2nd Flow Control Conference, AIAA, 2002, AIAA-2002-3274.Google Scholar
21. Lee, H-T.and Kroo, I.M. Computational Investigation of wings with miniature trailing edge control surfaces, 2nd AIAA Flow Control Conference, AIAA, 2004, AIAA-2004-2693.Google Scholar
22. van der Berg, J.W., Maseland, J.E.J. and Brandsma, F.J. Low speed maximum lift and flow control, Aerospace Science and Technology, 2004, 8, pp 389–400.Google Scholar
23. Lin, J.C. Review of research on low profile vortex generators to control boundary-layer separation, Progress in Aerospace Sciences, 2002, 38, pp 389–420.Google Scholar
24. Mahmood, G.I. and Ligrani, P.M. Heat transfer in a dimpled channel: combined influences of aspect ratio, Reynolds number and flow structure, Int J of Heat and Mass Transfer, 2002, 45, pp 2011–2020.Google Scholar
25. Chew, Y.T. and Khoo, B.C. Flow visualization studies on flow structures within spherical dimples of different depths with/without round edges, Proceeding of 5th PSFVIP, 2005, PSFVIP-5-280.Google Scholar
26. Isaev, S.A. and Leont’Ev, A.I. Numerical study of the eddy mechanism of enhancement of heat and mass transfer near a surface with a cavity, J Engineering Physics and Thermophysics, 1998, 71, (3), pp 481–487.Google Scholar
27. Isaev, S.A. and Leont’Ev, A.I. Identification of self-organized vortex like structures in numerically simulated turbulent flow of a viscous incompressible liquid streaming around a well on a plane, Technical Physics Letters, 2000, 26, (1), pp 15–18.Google Scholar
28. Isaev, S.A. and Leont’Ev, A.I. Modelling of the influence of viscosity on the tornado heat exchange in turbulent flow around a small hole on the plane, J Engineering Physics and Thermophysics, 2002, 75, (4), pp 890–898.Google Scholar
29. Isaev, S.A. and Leont’Ev, A.I. Numerical analysis of the influence of the depth of a spherical hole on a plane wall on turbulent heat exchange, J Engineering Physics and Thermophysics, 2003, 76, (1), pp 61–69.Google Scholar
30. Bunker, R.S. and M. Gotovskii, M. Heat transfer and pressure loss for flows inside converging channels with surface concavity effects, Proc of 4th Int Conf Compact Heat Exchangers and Enhancement Tech, Begell House, New York, US, 2003.Google Scholar
31. Ligrani, P.M. and Harrison, J.L. Flow structure due to dimple depressions on a channel surface, Physics of Fluids, 2001, 13, (11), pp 3442–3451.Google Scholar
32. Bearman, P.W. and Harvey, J.K. Golf ball aerodynamics, Aeronaut Q, 1976, 27, (2), pp 112–122.Google Scholar
33. Choi, J., Jeon, W-P. and Choi, H. Mechanism of drag reduction by dimples on a sphere, Physics of Fluids, 2006, 18, 041702, pp 1–4.Google Scholar
34. Lake, J.P. and King, P.I. Low Reynolds number loss reduction on turbine blades with dimples and V-Grooves, AIAA, 2000, AIAA-00-0738.Google Scholar
35. Rivir, R.B. and Sondergaard, R. Control of separation in turbine boundary-layers, 2nd AIAA Flow Control Conference, 2004, AIAA 2004-2201.Google Scholar
36. Davies, J.M. The aerodynamics of golf balls, J of Applied Physics, 1949, 20, (9), pp 821–828.Google Scholar
37. Ligrani, P.M., Won, S.Y. and Zhang, Q. Comparisons of flow structure above dimpled surface with different dimple depths in a channel, Phys of Fluids, 2005, 17, pp 3442–3452.Google Scholar
38. Won, S.Y. and Ligrani, P.M. Numerical predictions of flow structure and local Nusselt number ratios along and above dimpled surfaces with different dimple depths in a channel, Num. Heat Transfer (Part A), 2004, 46, pp 549–570 Google Scholar
39. Albrecht, H.E., Borys, M., Damanshke, N. and Tropea, C. Laser Doppler and Phase Doppler Measurement Techniques, Springer, New York, US, 2003.Google Scholar
40. Benedict, L.H. and Gould, R.D. Towards better uncertainty estimates for turbulence statistics, Exp in Fluids, 1996, 22, pp 129–136.Google Scholar
41. Kim, M.S. and Geropp, D. Experimental investigation of the ground effect on the flow around some two dimensional bluff bodies with ground effect, J Wind Engineering and Industrial Aerodynamics, 1998, 74-76, pp 511–519.Google Scholar
42. Raffel, M., Willert, C. and Kompenhaus, J. Particle Image Velocimetry: A Practicle Guide, Springer, New York, US, 1998.Google Scholar