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Effects of an axial flow on the centrifugal, elliptic and hyperbolic instabilities in Stuart vortices

Published online by Cambridge University Press:  10 October 2014

Manikandan Mathur*
Affiliation:
Department of Aerospace Engineering, Indian Institute of Technology Madras, Chennai 600036, India
Sabine Ortiz
Affiliation:
LadHyX, CNRS-École Polytechnique, F-91128 Palaiseau CEDEX, France UME/DFA, ENSTA, Chemin de la Hunière, 91761 Palaiseau CEDEX, France
Thomas Dubos
Affiliation:
Laboratoire de Météorologie Dynamique/IPSL, École Polytechnique, Palaiseau, France
Jean-Marc Chomaz
Affiliation:
LadHyX, CNRS-École Polytechnique, F-91128 Palaiseau CEDEX, France
*
Email address for correspondence: manims@ae.iitm.ac.in

Abstract

Linear stability of the Stuart vortices in the presence of an axial flow is studied. The local stability equations derived by Lifschitz & Hameiri (Phys. Fluids A, vol. 3 (11), 1991, pp. 2644–2651) are rewritten for a three-component (3C) two-dimensional (2D) base flow represented by a 2D streamfunction and an axial velocity that is a function of the streamfunction. We show that the local perturbations that describe an eigenmode of the flow should have wavevectors that are periodic upon their evolution around helical flow trajectories that are themselves periodic once projected on a plane perpendicular to the axial direction. Integrating the amplitude equations around periodic trajectories for wavevectors that are also periodic, it is found that the elliptic and hyperbolic instabilities, which are present without the axial velocity, disappear beyond a threshold value for the axial velocity strength. Furthermore, a threshold axial velocity strength, above which a new centrifugal instability branch is present, is identified. A heuristic criterion, which reduces to the Leibovich & Stewartson criterion in the limit of an axisymmetric vortex, for centrifugal instability in a non-axisymmetric vortex with an axial flow is then proposed. The new criterion, upon comparison with the numerical solutions of the local stability equations, is shown to describe the onset of centrifugal instability (and the corresponding growth rate) very accurately.

Type
Papers
Copyright
© 2014 Cambridge University Press 

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References

Bayly, B. J. 1986 Three-dimensional instability of elliptical flow. Phys. Rev. Lett. 57 (17), 21602163.CrossRefGoogle ScholarPubMed
Bayly, B. J. 1988 Three-dimensional centrifugal-type instabilities in inviscid two-dimensional flows. Phys. Fluids 31, 5664.Google Scholar
Bayly, B. J., Holm, D. D. & Lifschitz, A. 1996 Three-dimensional stability of elliptical vortex columns in external strain flows. Phil. Trans. R. Soc. Lond. A 354, 895926.Google Scholar
Bender, C. M. & Orszag, S. A. 1999 Advanced Mathematical Methods for Scientists and Engineers – Asymptotic Methods and Perturbation Theory. Springer.Google Scholar
Billant, P., Chomaz, J. M. & Huerre, P. 1998 Experimental study of vortex breakdown in swirling jets. J. Fluid Mech. 376, 183219.Google Scholar
Chicone, C. 2000 Ordinary Differential Equations with Applications. Springer.Google Scholar
Dubos, T., Barthlott, C. & Drobinski, P. 2008 Emergence and secondary instability of Ekman layer rolls. J. Atmos. Sci. 65, 23262342.Google Scholar
Eckhoff, K. S. 1984 A note on the instability of columnar vortices. J. Fluid Mech. 145, 417421.Google Scholar
Eckhoff, K. S. & Storesletten, L. 1978 A note on the stability of steady inviscid helical gas flows. J. Fluid Mech. 89, 401411.CrossRefGoogle Scholar
Friedlander, S. & Vishik, M. M. 1991 Instability criteria for the flow of an inviscid incompressible fluid. Phys. Rev. Lett. 66, 22042206.CrossRefGoogle ScholarPubMed
Gallaire, F. & Chomaz, J. M. 2003 Mode selection in swirling jet experiments: a linear stability analysis. J. Fluid Mech. 494, 223253.CrossRefGoogle Scholar
Gallaire, F., Rott, S. & Chomaz, J. M. 2004 Experimental study of a free and forced swirling jet. Phys. Fluids 16, 29072917.Google Scholar
Gallaire, F., Ruith, M., Meiburg, E., Chomaz, J. M. & Huerre, P. 2006 Spiral vortex breakdown as a global mode. J. Fluid Mech. 549, 7180.Google Scholar
Godeferd, F. S., Cambon, C. & Leblanc, S. 2001 Zonal approach to centrifugal, elliptic and hyperbolic instabilities in Stuart vortices with external rotation. J. Fluid Mech. 449, 137.Google Scholar
Hall, M. G. 1972 Vortex breakdown. Annu. Rev. Fluid Mech. 4, 195218.Google Scholar
Hattori, Y. & Fukumoto, Y. 2003 Short-wavelength stability analysis of thin vortex rings. Phys. Fluids 15 (10), 31513163.Google Scholar
Hattori, Y. & Fukumoto, Y. 2012 Effects of axial flow on the stability of a helical vortex tube. Phys. Fluids 24, 054102; 1–15.CrossRefGoogle Scholar
Hattori, Y. & Hijiya, K. 2010 Short-wavelength stability analysis of Hill’s vortex with/without swirl. Phys. Fluids 22, 074104; 1–8.Google Scholar
Healey, J. J. 2008 Inviscid axisymmetric absolute instability of swirling jets. J. Fluid Mech. 613, 133.CrossRefGoogle Scholar
Kerswell, R. R. 2002 Elliptical instability. Annu. Rev. Fluid Mech. 34, 83113.Google Scholar
Lacaze, L., Birbaud, A. L. & Le Dizès, S. 2005 Elliptic instability in a Rankine vortex with axial flow. Phys. Fluids 17, 017101; 1–5.Google Scholar
Leblanc, S. 1997 Stability of stagnation points in rotating flows. Phys. Fluids 9 (11), 35663569.Google Scholar
Leblanc, S. & Le Duc, A. 2005 The unstable spectrum of swirling gas flows. J. Fluid Mech. 537, 433442.Google Scholar
Le Dizès, S. & Eloy, C. 1999 Short-wavelength instability of a vortex in a multipolar strain field. Phys. Fluids 11, 500502.Google Scholar
Le Duc, A. & Leblanc, S. 1999 A note on Rayleigh stability criterion for compressible flows. Phys. Fluids 11, 35633566.Google Scholar
Leibovich, S. 1978 The structure of vortex breakdown. Annu. Rev. Fluid Mech. 10, 221246.Google Scholar
Leibovich, S. & Stewartson, K. 1983 A sufficient condition for the instability of columnar vortices. J. Fluid Mech. 126, 335356.Google Scholar
Liang, H. & Maxworthy, T. 2005 An experimental investigation of swirling jets. J. Fluid Mech. 525, 115159.Google Scholar
Lifschitz, A. & Hameiri, E. 1991 Local stability conditions in fluid dynamics. Phys. Fluids A 3 (11), 26442651.CrossRefGoogle Scholar
Lifschitz, A. & Hameiri, E. 1993 Localized instabilities of vortex rings with swirl. Commun. Pure Appl. Maths XLVI, 13791408.Google Scholar
Lifschitz, A., Suters, W. H. & Beale, J. T. 1996 The onset of instability in exact vortex rings with swirl. J. Comput. Phys. 129, 829.Google Scholar
Loiseleux, T., Chomaz, J.-M. & Huerre, P. 1998 The effect of swirl on jets and wakes: linear instability of the Rankine vortex with axial flow. Phys. Fluids 10, 11201134.Google Scholar
Oberleithner, K., Sieber, M., Paschereit, C. O., Petz, C., Hege, H. C., Noack, B. R. & Wygnanski, I. 2011 Three-dimensional coherent structures in a swirling jet undergoing vortex breakdown: stability analysis and empirical mode construction. J. Fluid Mech. 679, 383414.Google Scholar
Saffman, P. G. 1992 Vortex Dynamics. Cambridge University Press.Google Scholar
Stuart, J. T. 1967 On finite amplitude oscillations in laminar mixing layers. J. Fluid Mech. 29, 417440.Google Scholar