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Spatial development of trailing vortices behind a delta wing, in and out of ground effect

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Abstract

In this research, we study the dynamics of vortex pairs both in and out of ground effect. Trailing vortices are generated by towing a 75\(^\circ\) leading-edge sweep-angle delta wing in an XY-towing tank, at 15\(^\circ\) angle of attack. As the delta wing is towed, it generates a spatially developing vortex pair with the axial (streamwise) flow in the vortex cores. Particle image velocimetry is used to determine the transverse velocity field, and the vortex pair is found to be well-characterized by the superposition of two Lamb–Oseen vortices. The axial flow is captured using a longitudinal light sheet. To ensure we capture the vortex core, a technique is used wherein the light sheet is set such that it is slightly oblique to the length of the vortex. Using this technique allows the axial flow to be measured in the vortex core more than 20 chord-lengths downstream of the delta wing, capturing data at a resolution as close as 0.03 chord-lengths apart. This technique is unaffected by displacements of the vortex core, allowing us to analyze the axial flow profile both in and out of ground effect. A Gaussian velocity profile with a wake-like velocity deficit (flow upstream) is observed in the far-wake of the delta wing in both cases. We also trigger the long-wavelength instability (Crow AIAA J 8:2172–2179, 1970) in the vortices, and compare the measured growth rate of the instability to theoretical growth rate predictions using the theory of Widnall and Bliss (J Fluid Mech 50:335–353, 1971) in a similar manner to Leweke et al. (Annu Rev Fluid Mech 48:1–35, 2016) and Fabre (Ph.D Thesis, 2000). This work is limited to a chord-based Reynolds number of 5000.

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References

  • Anderson EA, Lawton TA (2003) Correlation ebtween vortex strength and axial velocity in a trailing vortex. J Aircr 40(4):699–704

    Article  Google Scholar 

  • Asselin DJ, Williamson CHK (2017) Influence of a wall on the three-dimensional dynamics of a vortex pair. J Fluid Mech 817:339–373

    Article  Google Scholar 

  • Batchelor GK (1964) Axial flow in trailing line vortices. J Fluid Mech 20(4):645–658

    Article  MathSciNet  Google Scholar 

  • Beresh SJ, Henfling JF, Spillers RW (2008) Planar velocimetry of a fin trailing vortex in subsonic compressible flow. In: 2008 Fluid dynamics conference, AIAA

  • Chen C, Wang Z, Gursul I (2018) Experiments on tip vortices interacting with downstream wings. Exp Fluids 59:82

  • Chigier NA, Corsihlia VR (1972) Wind-tunnel studies of wing wake turbulence. J Aircr 9(12):820–825

    Article  Google Scholar 

  • Ciffone DL, Orloff KL (1974) Axial flow measurements in trailing vortices. AIAA J 12(8):1154–1155

    Article  Google Scholar 

  • Crow SC (1970) Stability theory for a pair of trailing vortices. AIAA J 8(12):2172–2179

    Article  Google Scholar 

  • Dee FW, Nicholas OP (1968) Flight Measurements of wing-tip vortex motion near the ground. Technical report 1065, British Aeronautical Research Council

  • Del Pino C, Parras L, Felli M, Fernandez-Feria R (2011) Structure of trailing vortices: comparison between particle image velocimetry measurements and theoretical models. Phys Fluids 23(1):013602

  • Devenport WJ, Rife MC, Liapis SI, Follin GJ (1996) The structure and development of a wing-tip vortex. J Fluid Mech 312:67–106

    Article  MathSciNet  Google Scholar 

  • Fabre D (2000) Instabilités et instationnarités dans les tourbillons—-application aux sillages d’avions. PhD thesis, Université de Paris VI

  • Gad-el Hak M, Blackwelder RF (1985) The discrete vortices from a delta wing. AIAA J 23(6):961–962

    Article  Google Scholar 

  • Green SI (1995) Wing tip vortices. Fluid mechanics and its applications. Springer, Netherlands, pp 427–469

    Google Scholar 

  • Gursul I (2004) Recent developments in delta wing aerodynamics. Aeronaut J 2894:437–452

    Article  Google Scholar 

  • Harris DM, Williamson CHK (2012) Instability of secondary vortices generated by a vortex pair in ground effect. J Fluid Mech 700:148–186

    Article  Google Scholar 

  • Harvey JK, Perry FJ (1971) Flowfield produced by trailing vortices in the vicinity of the ground. AIAA J 9(8):1659–1660

    Article  Google Scholar 

  • Kumar A (1998) On the structure of vortex breakdown on a delta wing. Proc Math Phys Eng Sci R Soc 454:89–110

    Article  MathSciNet  Google Scholar 

  • Lamb H (1932) Hydrodynamics, 6th edn. Cambridge University Press, Cambridge

    MATH  Google Scholar 

  • Lee M, Ho CM (1989) Vortex dynamics of delta wings. In: Hak MG (ed) Frontiers in experimental fluid mechanics. Springer, Berlin, pp 365–427

    Chapter  Google Scholar 

  • Leweke T, Williamson CHK (2011) Experiments on long-wavelength instability and reconnection of a vortex pair. Phys Fluids 23:24101

    Article  Google Scholar 

  • Leweke T, LeDizès S, Williamson CHK (2016) Dynamics and instabilities of vortex pairs. Annu Rev Fluid Mech 48:1–35

    Article  MathSciNet  Google Scholar 

  • Miller GD (1997) Wakes of lifting and non-lifting bodies. PhD thesis, Cornell University

  • Miller GD, Williamson CHK (1996) Turbulence in the wake of a delta wing. In: Proceedings of sixth European turbulence conference, vol 36, pp 187–188

  • Moore DW, Saffman PG (1973) Axial flow in laminar trailing vortices. Proc R Soc Lond Ser A Math Phys Sci R Soc 333:491–508

    MATH  Google Scholar 

  • Morris SE, Williamson CHK (2019) Effect of a wall on three-dimensionally unstable trailing vortices from a delta wing. Phys Rev Fluids 4(10):100510

  • Morris SE, Williamson CHK (2020) Impingement of a counter-rotating vortex pair on a wavy wall. J Fluid Mech 895:A25

  • Ol MV, Gharib M (2003) Leading-edge vortex structure of non-slender delta wings at low Reynolds number. AIAA J 41(1):16–26

    Article  Google Scholar 

  • Orloff KL, Ciffone DL, Lorinez D (1973) Airfoil wake characteristics in the far field. Technical report 62318, NASA

  • Polhamus EC (1966) Sharp-edge delta wings based on a leading-edge-suction analogy. Technical report 1510.04455, NASA

  • Quaranta HU, Brynjell-Rahkola M, Leweke T, Henningson DS (2019) Local and global pairing instabilities of two itnerlaced helical vortices. J Fluid Mech 863:927–955

    Article  MathSciNet  Google Scholar 

  • Roy C, Leweke T, Thompson MC, Hourigan K (2011) Experiments on the elliptic instability in vortex pairs with axial core flow. J Fluid Mech 677:383–416

    Article  MathSciNet  Google Scholar 

  • Saffman PG (1993) Vortex dynamics. Cambridge monographs on mechanics. Cambridge University Press, Cambridge

    Google Scholar 

  • Schutt RR, Williamson CHK (2016) Unsteady sail dynamics due to bodyweight motions. In: The 22nd Chesapeake sailing yacht symposium, pp 58–72

  • Shekarriz A, Fu TC, Katz J (1993) Near-field behavior of a tip vortex. AIAA J 31(1):112–118

    Article  Google Scholar 

  • Spalart PR (1998) Airplane trailing vortices. Annu Rev Fluid Mech 30:107–138

    Article  MathSciNet  Google Scholar 

  • Thielicke W (2014a) PIVlab - time-resolved digital particle velocimetry tool for MATLAB. Version 1.40

  • Thielicke W, Stamhuis EJ (2014b) PIVlab - towards user-friendly, affordable and accurate digital particle image velocimetry in MATLAB. J Open Res Softw 2(1):e30

    Google Scholar 

  • Thielicke W, Stamhuis EJ (2014a) PIVlab—time-resolved digital particle image velocimetry tool for MATLAB

  • Thompson DH (1975) Experimental study of axial flow in wing tip vortices. J Aircr 12(11):910–911

    Article  MathSciNet  Google Scholar 

  • Tu H, Green MA, Marzanek M, Rival DE (2018) Experimental investigation of non-slender delta-wing planforms at low Reynolds numbers. In: 2018 Fluid dynamics conference, AIAA

  • Widnall SE (1975) The structure and dynamics of vortex filaments. Annu Rev Fluid Mech 7(1):141–165

    Article  Google Scholar 

  • Widnall SE, Bliss DB (1971) Slender-body analysis of the motion and stability of a vortex filament containing an axial flow. J Fluid Mech 50(2):335–353

    Article  Google Scholar 

  • Widnall SE, Bliss DB, Tsai CY (1974) The instability of short waves on a vortex ring. J Fluid Mech 66:35–47

    Article  MathSciNet  Google Scholar 

  • Williamson CHK, Leweke T, Miller GD (2000) Fundamental instabilities in spatially-developing wing wakes and temporally-developing vortex pairs. In: Hak MG (ed) Turbulence structure and vortex dynamics. Cambridge University Press, Cambridge

    Google Scholar 

  • Zehner P, Falissard F, Gloerfelt X (2018) Aeroacoustic study of the interaction of a rotating blade with a batchelor vortex. AIAA J 56(2):629–647

    Article  Google Scholar 

Download references

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Correspondence to Sarah E. Morris.

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Morris, S.E., Williamson, C.H.K. Spatial development of trailing vortices behind a delta wing, in and out of ground effect. Exp Fluids 61, 227 (2020). https://doi.org/10.1007/s00348-020-03058-7

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