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Experimental study of interfacial long waves in a two-layer shear flow

Published online by Cambridge University Press:  26 April 2006

Pierre Barthelet
Affiliation:
Institut de Mécanique des Fluides, 2, allée du Professeur C. Soula, 31400 Toulouse, France
François Charru
Affiliation:
Institut de Mécanique des Fluides, 2, allée du Professeur C. Soula, 31400 Toulouse, France
Jean Fabre
Affiliation:
Institut de Mécanique des Fluides, 2, allée du Professeur C. Soula, 31400 Toulouse, France

Abstract

Interfacial stability of two-layer Couette flow was investigated experimentally in a channel bent into an annular ring. This paper is focused on the supercritical long-wave instability which arises for a broad range of flow parameters. Above the critical upper plate velocity, a slowly growing long wave appears with wavelength equal to the perimeter of the channel. Transients of this wave were studied within the theoretical frame of amplitude equations obtained from the long-wave interface equation. Near the onset of instability, the unstable fundamental harmonic is described by the Landau–Stuart equation, and the nonlinear dynamics of the harmonics closely follows the central and slaved modes analysis. For the higher upper plate velocity, harmonics gain some autonomy but they eventually are enslaved by the fundamental, through remarkable collapses of amplitudes and phase jumps leading to wave velocity and frequency locking. Dispersive effects play a crucial role in the nonlinear dynamics. Far from the threshold, the second harmonic becomes unstable and bistability appears: the saturated wave is dominated either by the fundamental harmonic, or by the even harmonics, after periodic energy exchange.

Type
Research Article
Copyright
© 1995 Cambridge University Press

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References

Chang, H. C., Demekhin, E. A. & Kopelevich, D. I. 1993 Laminarizing effects of dispersion in an active-dissipative nonlinear medium. Physica D 63, 299.Google Scholar
Charles, M. E. & Lilleleht, L. U. 1965 An experimental investigation of stability and interfacial waves in a co-current flow two liquids. J. Fluid Mech. 22, 217.Google Scholar
Charru, F. 1991 Stabilité de l'interface entre deux fluids visquex. Thèese de Doctorat, Institut National Polytechnique de Toulouse.
Charru, F. & Fabre, J. 1994 Long waves at the interface between two viscous fluids. Phys. Fluids 6, 1223.Google Scholar
Charru, B. I., Krommes, J. A., Tang, W. M. & Rosenbluth, M. N. 1976 Non-linear saturation of the dissipative trapped-ion mode by mode coupling. Nucl. Fusion 16, 971.Google Scholar
Demekhin, E. A., Tokarev, G. Y. & Shkadov, V. YA. 1991 Hierarchy of bifurcations of spaceperiodic structures in a nonlinear model of active dissipative media. Physica D 52, 338.Google Scholar
Hinch, E. J. 1984 A note on the mechanism of the instability at the interface between two shearing fluids. J. Fluid Mech. 144, 463.Google Scholar
Hooper, A. P. 1985 Long-wave instability at the interface between two viscous fluids: Thin layer effects. Phys. Fluids 28, 1613.Google Scholar
Hooper, A. P. & Boyd, W. G. C. 1983 Shear-flow instability at the interface between two viscous fluids. J. Fluid Mech. 128, 507.Google Scholar
Hooper, A. P. & Boyd, W. G. C. 1987 shear flow instability due to a wall and a viscosity difference at the interface. J. Fluid Mech. 28, 37.Google Scholar
Kao, M. E. & Park, C. 1972 Experimental investigation of the stability of channel flow. J. Fluid Mech. 52, 401.Google Scholar
Kelly, R. E., Goussis, D. A., Lin, S. P. & Hsu, F. K. 1989 The mechanism for surface wave instability in film flow down an inclined plane. Phys. Fluids A 1, 819.Google Scholar
Kevrkidis, I. G., Nicolaenko, B. & Scovel, J. C. 1990 Back in the saddle again: a computer assisted study of the Kuramoto-Sivashinsky equations. SIAM J. Appl. Maths 50, 760.Google Scholar
Liu, J., Paul, J. D. & Gollub, J. P. 1993 Measurements of the primary instabilities of film flows. J. Fluid Mech. 250, 69.Google Scholar
Magnaudet, J., Rivero, M. & Fabre, J. 1995 Accelerated flows around a rigid sphere or a spherical bubble. Part l. Steady straining flow. J. Fluid Mech. 284, 97.Google Scholar
Manneville, P. 1990 Dissipative Structures and Weak Turbulence. Academic.
Mewell, A. C., Passot, T. & Legal, J. 1983 wave modulation and breakdown. J. Fluid Mech. 128, 489.Google Scholar
Newell, A. C., Passot, T. & Legal, J. 1993 Order parameter equations for patterns. Ann. Rev. Fluid Mech. 25, 399.Google Scholar
Renardy, Y. 1985 Instability at the interface between two shearing fluids in a channel. Phys. Fluids 28, 3441.Google Scholar
Renardy, Y. 1987 The thin layer effect and interfacial stability in a two-layer Couette flow with similar liquids. Phys. Fluids 30, 1627.Google Scholar
Renardy, Y. 1989 Weakly nonlinear behavior of periodic disturbances in two layer Couette-Poiseuille flow. Phys. Fluids A 1, 1666.Google Scholar
Shlang, T., Sivashinski, G. I., Babchin, A. J. & Frenkel, A. L. 1985 Irregular wavy flow due to visco us stratification. J. Phys. Paris 46, 863.Google Scholar
Smith, M. K. 1990 The mechanism for the long-wave instability in thin liquid films. J. Fluid Mech. 217, 469.Google Scholar
Tilley, B. S., Davis, S. H. & Bankoff, S. G. 1994 Nonlinear long-wave stability of superposed fluids in an inclined channel. J. Fluid Mech. 277, 55.Google Scholar
Yiantsios, S. G. & Higgins, B. G. 1988 Linear stability of plane Poiseuille flow of two superposed fluids. Phys. Fluids 31, 3225.Google Scholar
Yih, C. S. 1967 Instability due to viscous stratification. J. Fluid Mech. 27, 337.Google Scholar