Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-06T11:44:15.246Z Has data issue: false hasContentIssue false
  • English
  • Français

The effect of skewing on the vorticity produced by an airjet vortex generator

Published online by Cambridge University Press:  04 July 2016

A. A. Barberopoulos  and
K. P. Garry
A. A. Barberopoulos
Affiliation:
Flow Control and Prediction GroupCollege of AeronauticsCranfield University Bedfordshire, UK
K. P. Garry
Affiliation:
Flow Control and Prediction GroupCollege of AeronauticsCranfield University Bedfordshire, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

The vorticity production by a single vortex generator jet in a turbulent boundary layer at high speed and zero pressure gradient was studied by analysing surface-flow patterns. The investigation involved a range of jet mass flow rates and skew angles while the freestream Mach number and jet pitch angle were held constant. A qualitative analysis of the skin friction patterns demonstrated the effective role of the skew angle as a bifurcation parameter. The vortex production is classified into three main regimes as the skew angle increases from zero (fully downstream) to 180° (fully upstream). Better understanding of the physical mechanism behind the transition from the first regime to the second is crucial in the design of the airjet vortex generator.

Type
Research Article
Information
The Aeronautical Journal , Volume 102 , Issue 1013 , March 1998 , pp. 171 - 177
Copyright
Copyright © Royal Aeronautical Society 1998 

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. Wallis, R.A. The use of air jets for boundary layer control, Technical Note ARL Aero Note 110, Australia, 1952.Google Scholar
2. Wallis, R.A. A preliminary note on a modified type of air jet for boundary layer control, Report ARC CP 513, 1960.Google Scholar
3. Wallis, R.A. and Stuart, C.M. On the control of shock-induced boundary layer separation with discrete air jets, Report ARC CP 595 1962.Google Scholar
4. Zhang, S. and Li, F. Experiments about the air jet vortex generator, In prodeedings of 8th Institute of Aeronautics and Astronautics, Cincinnati, Ohio, 1987, pp 513–516.Google Scholar
5. Johnston, J. and Nishi, M. Vortex generator jets-a means for passive and active control of boundary layer separation, Paper AIAA-89-0564, 1989.Google Scholar
6. Selby, G. Experimental parametric study of jet vortex generators for flow separation control, Final report NASA CR 187836, Dec 31 1990.Google Scholar
7. Selby, G., Lin, J.C. and Howard, F.G. Control of low-speed turbulent separated flow using jet vortex generators, Exp in Fluids, 1992, 12, (6), pp 394–400.Google Scholar
8. Compton, D.A. and Johnston, J.P. Streamwise vortex production by pitched and skewed jets in a turbulent boundary layer, Paper AIAA-91-0038, 1991.Google Scholar
9. Pearcey, H.H. Shock-induced separation and its prevention by design and boundary layer control, Lachmann, G. (Ed), Boundary Layer and Flow Control, Pergamon Press, Oxford, 1961.Google Scholar
10. Pearcey, H.H., Rao, K. and Sykes, D.M. Inclined airjets used as vortex generators to suppress shock-induced separation. In AGARD Fluid Dynamics Panel Symposium, Winchester, UK, April 1993.Google Scholar
11. Le Grives, E. Mixing process induced by the vorticity associated with the penetration of a jet into a cross flow. Paper ONERA TP-77/2, 1977.Google Scholar
12. Morton, B.R. The generation and decay of vorticity, Geophys Astrophys Fluid Dynamics, 1984, 28, (1), pp 277–308.Google Scholar
13. Maltby, R.L. (Ed) Flow visualisation in windtunnels using indicators, collection of reports, AGARDograph 70, 1962.Google Scholar
14. Hunt, J.C.R., Abell, C.J., Peterka, J.A. and Woo, H. Kinematical studies of the flows around free or surface-mounted obstacles; applying topology to flow visualisation, J of Fluid Mech, 1978, 86, (1), pp 179–200.Google Scholar
15. Tobak, M. and Peake, D.J. Topology of three-dimensional separated flows, technical memorandum, NASA TM 81294, 1981.Google Scholar
16. Barker, P.G. Bifurcations in flow patterns, some applications of the qualitative theory of differential equations in fluid dynamics. Technische Universiteit Delft 1988.Google Scholar
17. Baker, C.J. The laminar horsehoe vortex, J of Fluid Mech, 1979, 95, (2), pp 347–367.Google Scholar
18. Krothapalli, A. and Lourenco, L. On the separated flow upstream of a jet in a cross flow, Paper AIAA-89-0571, 1989.Google Scholar
19. Delery, J.M. Aspects of vortex breakdown, Prog Aerospace Sci, 1994, 30, pp 1–59.Google Scholar
20. Dallmann, U. Topological structures of three-dimensional vortex flow separation, Paper AIAA-83 1735, 1991.Google Scholar
21. Perry, A.E. and Chong, M.S. A series-expansion study of the Navier-Stokes equations with applications to three-dimensional separation patterns, J of Fluid Mech, 1986, 173, (1), pp 207–223.Google Scholar
22. Kelso, R.M., Lim, T.T. and Perry, A.E. An experimental study of round jets in cross-flow, J of Fluid Mech, 1996, 306, (1), pp 111–144.Google Scholar