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Effect of tracer particle characteristics on visualisation of delta wing vortices

Published online by Cambridge University Press:  04 July 2016

D. I. Greenwell
D. I. Greenwell*
Affiliation:
QinetiQ Bedfordshire, UK
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Abstract

Preliminary investigations of the effect of tracer particle characteristics on flow visualisation in a steady delta wing leading-edge vortex are presented, using both 3D simulations of particle trajectories and a simplified analysis of the radial equilibrium conditions. It is shown that many of the flow structures apparently seen in wind and water tunnel visualisation studies of delta wing vortices may in fact be artefacts of the tracer particle characteristics. In particular the ‘smoke tube’ or ‘hole’ effect often seen in smoke flow visualisation in wind tunnels does not (contrary to popular usage) indicate the size of the viscous subcore, and is not a reliable indicator of the vortex structure. The implications for both visualisation studies and optical flow measurement techniques are discussed.

Type
Research Article
Information
The Aeronautical Journal , Volume 106 , Issue 1063 , September 2002 , pp. 473 - 482
Copyright
Copyright © Royal Aeronautical Society 2002 

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References

1. Payne, F.M. Ng, T.T. and Nelson, R.C. Visualisation of leading edge vortices on a series of flat plate delta wings, NASA CR 4320, 1991.Google Scholar
2. Maltby, R.L. Engler, P.B. and Keating, R.F.A. Some exploratory measurements of leading-edge vortex positions on a delta wing oscillating in heave, ARC R&M 3410, July 1963.Google Scholar
3. Maltby, R.L. and Keating, R.F.A. Flow visualisation in low-speed wind tunnels-current British practice, RAE Tech Note (Aero) 2715, August 1960.Google Scholar
4. Campbell, J.F. and Chambers, J.R. Patterns in the sky: Natural visualisation of aircraft flow fields, NASA SP-514.Google Scholar
5. Visser, K.D. Nelson, R.C. and Ng, T.T. Method of cold smoke generation for vortex core tagging, J Aircr, November 1988, 25 (11), pp 1069–1071.Google Scholar
6. Lambourne, N.C. and Bryer, D.W. The bursting of leading-edge vortices-some observations and discussion of the phenomenon, ARC R&M 3282, April 1961.Google Scholar
7. Elle, B.J. An investigation at low speed of the flow near the apex of thin delta wings with sharp leading edges, ARC R&M 3176, January 1968.Google Scholar
8. Greenwell, D.I. and Gursul, I. Effect of tracer particle characteristics on visualisation of delta wing vortices, paper 111, 9th International Symposium on Flow Visualisation, Edinburgh, August 2000.Google Scholar
9. Hale, R.W. Tan, P. and Ordway, D.E. Experimental investigation of several neutrally-buoyant bubble generators for aerodynamic flow visualisation, Naval Research Review, June 1971, 24 (6), pp 19–24.Google Scholar
10. Verhaagen, N.G. An experimental investigation of the vortex flow over delta and double-delta wings at low speed, paper 7 in ‘Aerodynamics of Vortical Type Flows in Three Dimensions’, AGARD-CP-342,1983.Google Scholar
11. Erickson, G.E. Vortex flow correlation, AFWAL-TR-80-3143, January 1981.Google Scholar
12. Vorropoulus, G. and Wendt, J.F. Laser velocimetry study of com pressibility effects on the flow field of a delta wing, paper 9 in ‘Aerodynamics of Vortical Type Flows in Three Dimensions’, AGARD-CP-342,1983.Google Scholar
13. Gursul, I. Lusseyran, D. and Rockwell, D. On interpretation of flow visualisation of unsteady shear flows, Experiments in Fluids, 1990, 9, pp 257–266.Google Scholar
14. Hall, M.G. A theory for the core of a leading edge vortex, J Fluid Mechanics, 1961, 11, pp 209–228.Google Scholar
15. Visser, D. An Experimental Analysis of Critical Factors Involved in the Breakdown Process of Leading Edge Vortex Flows, PhD Thesis, University of Notre Dame, April 1991.Google Scholar
16. Kerho, M.F. and Bragg, M.B. Neutrally buoyant bubbles used as flow tracers in air, Experiments in Fluids, 1994, 16 (6), pp 393–400.Google Scholar
17. Sridar, G. and Katz, J. Effect of entrained bubbles on the structure of vortex rings, J Fluid Mechanics, 1999, 397, pp 171–202.Google Scholar
18. Lowson, M.V. The three dimensional vortex sheet structure on delta wings, paper 11 in ‘Fluid Dynamics of Three-Dimensional Turbulent Shear Flows’, AGARD-CP-438, October 1988.Google Scholar
19. Gursul, I. Criteria for location of vortex breakdown over delta wings, Aeronaut J, May 1995, 99, (985), pp 194–196.Google Scholar
20. Brandon, J.M., Hallissy, J.B., Brown, P.W. and Lamar, J.E. In flight flow visualisation results of the F-106B with a vortex flap, paper A-43, NATO RTO Symposium on ‘Advanced Flow Management’, Loen, Norway, May 2001.Google Scholar
21. Thompson, D.H. A water tunnel study of vortex breakdown over wings with highly swept leading edges, Aerodynamics Note 356, Australian Defence Scientific Research Laboratories, May 1975.Google Scholar
22. Leishman, J.G. Seed particle dynamics in tip vortex flows, J Aircr, July-August 1996, 33, (4), pp 823–825.Google Scholar