Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-17T13:18:20.615Z Has data issue: false hasContentIssue false

Linear stability of a viscoelastic liquid flow on an oscillating plane

Published online by Cambridge University Press:  31 May 2017

Arghya Samanta*
Affiliation:
Department of Applied Mechanics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
*
Email address for correspondence: [email protected]

Abstract

Linear stability of a viscoelastic liquid on an oscillating plane is studied for disturbances of arbitrary wavenumbers. The main aim is to extend the earlier study of Dandapat & Gupta (J. Fluid Mech., vol. 72, 1975, pp. 425–432) to the finite wavenumber regime, which has not been attempted so far in the literature. The Orr–Sommerfeld boundary value problem is formulated for an unsteady base flow, and it is resolved numerically based on the Chebyshev spectral collocation method along with the Floquet theory. The analytical solution predicts that U-shaped unstable regions appear in the separated bandwidths of the imposed frequency, and the dominant mode of the long-wave instability intensifies in the presence of the viscoelastic parameter. The numerical solution shows that oblique neutral curves come out from the branch points of the U-shaped neutral curves at finite wavenumber and continue with the imposed frequency until the curves cross the next U-shaped neutral curve. As a consequence, in the finite wavenumber regime, no stable bandwidth of the imposed frequency is predicted by the long-wavelength analysis. Further, in some frequency ranges, the finite wavenumber instability is more dangerous than the long-wave instability.

Type
Papers
Copyright
© 2017 Cambridge University Press 

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

Andersson, H. I. & Dahl, E. N. 1999 Gravity-driven flow of a viscoelastic liquid film along a vertical wall. J. Phys. D: Appl. Phys. 32, 15571562.Google Scholar
Barnes, H. A., Hutton, J. F. & Walters, K. 1989 An Introduction to Rheology. Elsevier.Google Scholar
Beard, D. W. & Walters, K. 1964 Elastico-viscous boundary-layer flows I. Two-dimensional flow near a stagnation point. Proc. Camb. Phil. Soc. 60, 667674.Google Scholar
Bird, R. B., Curtiss, C. F., Armstrong, R. C. & Hassager, O. 1987 Dynamics of Polymer Liquids, vols. 1 and 2. Wiley.Google Scholar
Burya, A. G. & Shkadov, V. Ya. 2001 Stability of a liquid film flowing down an oscillating inclined surface. Fluid Dyn. 36, 671681.Google Scholar
Dandapat, B. S. & Gupta, A. S. 1975 Instability of a horizontal layer of viscoelastic liquid on an oscillating plane. J. Fluid Mech. 72, 425432.Google Scholar
Dávalos-Orozco, L. A. 2013 Stability of thin viscoelastic flims down wavy walls. Interfacial Phenomena Heat Transfer 1, 301315.Google Scholar
Gao, P. & Lu, X.-Y. 2006 Effect of surfactants on the long-wave stability of oscillatory film flow. J. Fluid Mech. 562, 345354.Google Scholar
Gao, P. & Lu, X.-Y. 2008 Instability of an oscillatory fluid layer with insoluble surfactants. J. Fluid Mech. 595, 461490.Google Scholar
Grotberg, J. B. & Jensen, O. E. 2004 Biofluid mechanics in flexible tubes. Annu. Rev. Fluid Mech. 36, 121147.Google Scholar
Huang, C.-T. & Khomami, B. 2001 The instability mechanism of single and multi-layer Newtonian and viscoelastic flows down an inclined plane. Rheol. Acta 40, 467484.Google Scholar
Ikbal, Md. A. 2012 Viscoelastic blood flow through arterial stenosis – effect of variable viscosity. Intl J. Non-Linear Mech. 47, 888894.Google Scholar
Larson, R. G. 1992 Instabilities in viscoelastic flows. Rheol. Acta 31, 213263.Google Scholar
Lin, S. P., Chen, J. N. & Woods, D. R. 1996 Suppression of instability in a liquid film flow. Phys. Fluids 8, 32473252.Google Scholar
Oldroyd, J. G. 1950 On the formulation of rhelogical equations of state. Proc. R. Soc. Lond. A 200, 523541.Google Scholar
Or, A. C. 1997 Finite-wavelegth instability in a horizontal liquid layer on an oscillating plane. J. Fluid Mech. 335, 213232.Google Scholar
Or, A. C. & Kelly, R. E. 1998 Thermocapillary and oscillatory-shear instabilities in a layer of liquid with a deformable surface. J. Fluid Mech. 360, 2139.Google Scholar
Samanta, A. 2009 Effect of electric field on the stability of an oscillatory contaminated film flow. Phys. Fluids 21, 114101.Google Scholar
Savins, J. G. 1967 A stress-controlled drag-reduction phenomenon. Rheol. Acta 6, 323330.Google Scholar
Schmid, P. & Henningson, D. 2001 Stability and Transition in Shear Flows. Springer.Google Scholar
Shaqfeh, E. S. G. 1996 Purely elastic instabilities in viscometric flows. Annu. Rev. Fluid Mech. 28, 129185.Google Scholar
Smith, M. K. 1990 The mechanism for the long-wave instability in thin liquid films. J. Fluid Mech. 217, 469485.Google Scholar
Walters, K. 1960 The motion of an elastico-viscous liquid contained between coaxial cylinders (II). Q. J. Mech. Appl. Maths 13, 444461.Google Scholar
Wei, H. H. 2005 Stability of a viscoelastic falling film with surfactant subject to an interfacial shear. Phys. Rep. 71, 066306.Google Scholar
Woods, D. R. & Lin, S. P. 1995 Instability of a liquid film flow over a vibrating inclined plane. J. Fluid Mech. 294, 391407.Google Scholar
Yih, C. S. 1968 Instability of unsteady flows or configurations. Part 1. Instability of a horizontal liquid layer on an oscillating plane. J. Fluid Mech. 31, 737751.Google Scholar