Hostname: page-component-77c89778f8-n9wrp Total loading time: 0 Render date: 2024-07-17T03:56:38.891Z Has data issue: false hasContentIssue false
  • English
  • Français

Studies of the flow field near a IMACA 4412 aerofoil at nearly maximum lift

Published online by Cambridge University Press:  04 July 2016

R. C. Hastings  and
B. R. Williams
R. C. Hastings
Affiliation:
Aerodynamics Department, Royal Aircraft Establishment, Farnborough
B. R. Williams
Affiliation:
Aerodynamics Department, Royal Aircraft Establishment, Farnborough
Get access Rights & Permissions [Opens in a new window]

Summary

Measurements made at a Mach number of 0.18 and a chord-based Reynolds number of 4·2 x 106 on a constant-chord model having a NACA 4412 aerofoil section are described and compared with the results of flow field calculations.

Both the experimental arrangement and the difficulties initially experienced in achieving an adequate approximation to two-dimensional flow above the wing are briefly outlined.

The measurements include static pressure distributions on the wing surface and on the wind-tunnel walls above and below the mid-span section of the wing. The main emphasis in the experiment was, however, on defining the development of the upper surface boundary layer through separation (at about 20% chord ahead of the trailing-edge) and on into the wake, making extensive use of laser anemometry to measure mean velocities. In addition, Reynolds stresses were measured in certain parts of the flow field by hot-wire anemometry.

The flow field calculations are of the semi-inverse kind in which an inverse momentum-integral treatment of the shear flow, used to avoid difficulties at separation, is coupled to a direct solution of the inviscid flow problem. The main features of the method are outlined.

Type
Research Article
Information
The Aeronautical Journal , Volume 91 , Issue 901 , January 1987 , pp. 29 - 44
Copyright
Copyright © Royal Aeronautical Society 1987 

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. Lock, R. C. and Firmin, M. C. P. Survey of techniques for estimating viscous effects in external aerodynamics. Numerical Methods in Aeronautical Fluid Dynamics, ed. Roe, P. L., Academic Press, 1982.Google Scholar
2. Williams, B. R. The prediction of separated flow using a viscous-inviscid interaction method. The Aeronautical Journal of the Royal Aeronautical Society, May 1985, 185–197.Google Scholar
3. Wadcock, A. J. Flying hot-wire study of a two-dimensional turbulent separation on a NACA 4412 aerofoil at maximum lift. PhD thesis, California Institute of Technology, 1978.Google Scholar
4. Hastings, R. C., Moreton, K. G. and Clark, R. Mean flow properties measured around an aerofoil close to its maximum lift. Paper 14-1. 2nd Int. Symp. on Appl. of Laser Anemometry to Fluid Mechanics, Lisbon. 2nd-4th July 1984.Google Scholar
5. Winkelmann, A. E. On the occurrence of mushroom shaped stall cells in separated flow. AIAA Paper 83-1734, 1983.Google Scholar
6. Lovell, D. A. An automatic wake traverse system for flow field measurements in large low-speed wind tunnels. RAE TR 80078, 1980.Google Scholar
7. Ashill, P. R. and Weeks, D. J. A method for determining wall-interference corrections in solid-wall tunnels from measurements of static pressure at the walls. Paper 1, AGARD CP No 335, 1982.Google Scholar
8. Smith, F. T. Interacting flow theory and trailing edge separations — no stall, 1983, J Fluid Mech, 131, 219–249.Google Scholar
9. East, L. F. A representation of second-order boundary layer effects in the momentum integral equation and in viscous- inviscid interactions. RAE TR 81002, 1981.Google Scholar
10. Green, J. E. Two-dimensional turbulent reattachment as a boundary layer problem. Paper 16, AGARD CP No 4, 1966.Google Scholar
11. Kline, S. J. Bardina, J. and Strawn, R. Correlation and computation of detachment and reattachment of turbulent boundary layers on two-dimensional faired surfaces. A1AA-81- 1220, 1981.Google Scholar
12. East, L. F. Smith, P. D. and Merryman, P. J. Prediction of the development of separated turbulent boundary layers by the lag-entrainment method. RAE TR 77046. 1977.Google Scholar
13. Green, J. E., Weeks, D. J. and Brooman, J. W. F. Prediction of turbulent boundary layers and wakes in compressible flow by a lag-entrainment method. ARC R & M 3791, 1977, also RAE TR 72231, 1972.Google Scholar
14. Carter, J. E. A new boundary layer inviscid interaction technique for separated flows. AIAA-79-1450, 1979.Google Scholar
15. Le Balleur, J. C. Couplage visqueux — non visqueux; mèthode numérique et applications aux écoulements bidimensionnels transsoniques et supersoniques. La Recherche Aérospatiale, 1978-2, 1978.Google Scholar
16. Williams, B. R. The calculation of separated flows for a two- dimensional aerofoil at low speed. RAE TR to be published.Google Scholar
17. Newling, J. C. An improved two-dimensional multi-aerofoil program. HSA-MAE-R-FOM-0007, 1977.Google Scholar
18. Weeks, D. J. RAE unpublished paper.Google Scholar
19. Le Balleur, J. C. Strong matching method for computing transonic viscous flows including wakes and separations on lifting aerofoils. La Recherche Aerospatiale, 1981-3 1981.Google Scholar
20. Lock, R. C. Private communication.Google Scholar
21. Green, J. E.. The prediction of turbulent boundary layer development in compressible flows. J Fluid Mech, 1968, 31, 753–778.Google Scholar
22. Wigton, L. B. and Holt, M. Viscous-inviscid interaction in transonic flow. AIAA-81-1003, 1981.Google Scholar
23. Thwaites, B. (Ed). Incompressible aerodynamics. Clarendon Press, 1960.Google Scholar
24. Granville, P. S. The calculation of viscous drag of bodies of revolution. David Taylor Model Basin, Report 849, 1953.Google Scholar
25. Horton, H. P. A semi-empirical theory for the growth and bursting of laminar separation bubbles. ARC CP 1673, 1967.Google Scholar