Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-14T17:20:59.049Z Has data issue: false hasContentIssue false

Downstream evolution of wingtip vortices produced from an inverted wing

Published online by Cambridge University Press:  27 January 2016

P. Kurts
Affiliation:
School Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, Australia

Abstract

Counter-rotating vortices form from the opposite edges of lifting surfaces, and gradually move laterally and dissipate as they travel downstream (as seen in a wing-fixed reference frame). Under ground effect conditions, the vortex from a lifting wing – such as that used in an aircraft application – moves laterally outboard from the wingtip as it progresses downstream; for a downforce wing in ground effect – such as that used in an automotive application – the vortex moves laterally inboard. An interesting case is the situation where the inboard moving vortices become in close proximity to each other. The objective of the present study was to investigate counter-rotating vortices produced from a low aspect ratio downforce wing operating in ground effect. The pair of vortices move towards each other and mutually induce an upwards directed motion which in turn reduces the inboard movement driven by the ground effect. Experimental data gained from three-dimensional Laser Doppler Anemometry in a moving ground wind-tunnel was used to validate a Large Eddy Simulation computational result.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2015

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.Barber, T.Visualisation of wingtip vortices produced by a wing near a stationary ground plane, Int J Aerodynamics, 2010, 1, (1), pp 1827.CrossRefGoogle Scholar
2.Devenport, W.J., Zsoldos, J.S. and Vogel, C.M.The structure and development of a counter-rotating wing-tip vortex pair, J Fluid Mechanics, 1997, 332, 71, p 104.CrossRefGoogle Scholar
3.Gerontakos, P. and Lee, T.Near-eld tip vortex behind a swept wing model, Experiments in Fluids, 2006, 40, (1), pp 141155.CrossRefGoogle Scholar
4.Cerretelli, C. and Williamson, C.H.K.The physical mechanism for vortex merging, J Fluid Mechanics, 2003, 475, (1), pp 4177.CrossRefGoogle Scholar
5.Holzäapfel, F. and Steen, M.Aircraft wake-vortex evolution in ground proximity: analysis and parameterization. AIAA J, 2007, 45, (1), pp 218.CrossRefGoogle Scholar
6.Crow, S.C.Stability theory for a pair of trailing vortices, AIAA J, 1970, 8, (12), pp 21722179.CrossRefGoogle Scholar
7.Spalart, P.R.Airplane trailing vortices, Annual Review of Fluid Mechanics, 1998, 30, (1), pp 107138.CrossRefGoogle Scholar
8.Panaras, A. and Voutsinas, S.G.Eect of counter-rotating vortices on the development of aircraftwakes, Aeronaut J, 2004, 108, (1089), pp 585592.CrossRefGoogle Scholar
9.Misaka, T., Holzäapfel, F., Hennemann, I., Gerz, T., Manhart, M. and Schwertfirm, F.Vortex bursting and tracer transport of a counter-rotating vortex pair, Physics of Fluids, 2012, 24, (2), 025104.CrossRefGoogle Scholar
10.Beves, C.An Investigation Into The Use of Low Aspect Ratio Spherical Wells T Reduce The Low Separation on an Inverted Wing in Ground Eect. PhD thesis, University of New South Wales, Sydney Australia, 2009.Google Scholar
11.Devenport, W.J., Rife, M.C., Liapis, S.I. and Follin, G.J.The structure and development of a wing-tip vortex, J Fluid Mechanics, 1996, 312, (67), p 106.CrossRefGoogle Scholar
12.Diasinos, S., Beves, C.C. and Barber, T.J.Alignment technique for three-dimensional laser Doppler anemometry, Measurement Science and Technology, 2012, 24, (1-5).Google Scholar
13.Lilly, D.K.A proposed modication of the Germano subgrid-scale closure method, Physics of Fluids, 1992, 4, (633635).CrossRefGoogle Scholar
14.Geurts, B., Geurts, B.J. and Geurts, B.J.Elements of direct and large-eddy simulation, R.T. Edwards, Philadelphia, Pennsylvania, USA, 2004.Google Scholar
15.Barber, T.J., Leonardi, E. and Archer, R.D.Causes for discrepancies in ground eect analyses. Aeronaut J, 2002, 106, (1066), pp 653667.CrossRefGoogle Scholar
16.Green, S.I. and Acosta, A.J.Unsteady ow in trailing vortices. J Fluid Mechanics, 1991, 227, 107, p 134.CrossRefGoogle Scholar
17.Zheng, Z.C. and Ash, R.L.Study of aircraft wake vortex behavior near the ground. AIAA J, 1996, 34, (3), pp 580589.CrossRefGoogle Scholar
18.Heyes, A.L., Jones, R.F. and Smith, D.A.R.Wandering of wing-tip vortices. In Proceedings of 12th international symposium on the applications of laser techniques to fuid mechanics. Lisbon, Portugal, 2004.Google Scholar